A phylogeny and revised classification of Squamata, including 4161
Transcription
A phylogeny and revised classification of Squamata, including 4161
A phylogeny and revised classification of Squamata, including 4161 species of lizards and snakes Pyron et al. Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 RESEARCH ARTICLE Open Access A phylogeny and revised classification of Squamata, including 4161 species of lizards and snakes R Alexander Pyron1*, Frank T Burbrink2,3 and John J Wiens4 Abstract Background: The extant squamates (>9400 known species of lizards and snakes) are one of the most diverse and conspicuous radiations of terrestrial vertebrates, but no studies have attempted to reconstruct a phylogeny for the group with large-scale taxon sampling. Such an estimate is invaluable for comparative evolutionary studies, and to address their classification. Here, we present the first large-scale phylogenetic estimate for Squamata. Results: The estimated phylogeny contains 4161 species, representing all currently recognized families and subfamilies. The analysis is based on up to 12896 base pairs of sequence data per species (average = 2497 bp) from 12 genes, including seven nuclear loci (BDNF, c-mos, NT3, PDC, R35, RAG-1, and RAG-2), and five mitochondrial genes (12S, 16S, cytochrome b, ND2, and ND4). The tree provides important confirmation for recent estimates of higher-level squamate phylogeny based on molecular data (but with more limited taxon sampling), estimates that are very different from previous morphology-based hypotheses. The tree also includes many relationships that differ from previous molecular estimates and many that differ from traditional taxonomy. Conclusions: We present a new large-scale phylogeny of squamate reptiles that should be a valuable resource for future comparative studies. We also present a revised classification of squamates at the family and subfamily level to bring the taxonomy more in line with the new phylogenetic hypothesis. This classification includes new, resurrected, and modified subfamilies within gymnophthalmid and scincid lizards, and boid, colubrid, and lamprophiid snakes. Keywords: Amphisbaenia, Lacertilia, Likelihood support measures, Missing data, Serpentes, Squamata, Phylogenetics, Reptilia, Supermatrices, Systematics Background Squamate reptiles (lizards, snakes, and amphisbaenians ["worm lizards"]) are among the most diverse radiations of terrestrial vertebrates. Squamata includes more than 9400 species as of December 2012 [1]. The rate of new species descriptions shows no signs of slowing, with a record 168 new species described in 2012 [1], greater than the highest yearly rates of the 18th and 19th centuries (e.g. 1758, 118 species; 1854, 144 species [1]). Squamates are presently found on every continent except Antarctica, and in the Indian and Pacific Oceans, and span many diverse ecologies and body forms, * Correspondence: rpyron@colubroid.org 1 Department of Biological Sciences, The George Washington University, 2023 G St. NW, Washington, DC 20052, USA Full list of author information is available at the end of the article from limbless burrowers to arboreal gliders (summarized in [2-4]). Squamates are key study organisms in numerous fields, from evolution, ecology, and behavior [3] to medicine [5,6] and applied physics [7]. They have also been the focus of many pioneering studies using phylogenies to address questions about trait evolution (e.g. [8,9]). Phylogenies are now recognized as being integral to all comparative studies of squamate biology (e.g. [10,11]). However, hypotheses about squamate phylogeny have changed radically in recent years [12], especially when comparing trees generated from morphological [13-15] and molecular data [16-20]. Furthermore, despite extensive work on squamate phylogeny at all taxonomic levels, a large-scale phylogeny (i.e. including thousands of species and multiple genes) has never been attempted using morphological or molecular data. © 2013 Pyron et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Squamate phylogenetics has changed radically in the last 10 years, revealing major conflicts between the results of morphological and molecular analyses [12]. Early estimates of squamate phylogeny [21] and recent studies based on morphological data [13-15,22] consistently supported a basal division between Iguania (including chameleons, agamids, and iguanids, sensu lato), and Scleroglossa, which comprises all other squamates (including skinks, geckos, snakes, and amphisbaenians). Within Scleroglossa, many phylogenetic analyses of morphological data have also supported a clade containing limb-reduced taxa, including various combinations of snakes, dibamids, amphisbaenians, and (in some analyses) limb-reduced skinks and anguids [13-15,19,22], though some of these authors also acknowledged that this clade was likely erroneous. In contrast, recent molecular analyses have estimated very different relationships. Novel arrangements include placement of dibamids and gekkotans near the root of the squamate tree, a sister-group relationship between amphisbaenians and lacertids, and a clade (Toxicofera) uniting Iguania with snakes and anguimorphs within Scleroglossa [16-20,23,24]. These molecular results (and the results of combined morphological and molecular analyses) suggest that some estimates of squamate phylogeny based on morphology may have been misled, especially by convergence associated with adaptations to burrowing [19]. However, there have also been disagreements among molecular studies, such as placement of dibamids relative to gekkotans and other squamates, and relationships among snakes, iguanians, and anguimorphs (e.g. [17,20]). Analyses of higher-level squamate relationships based on molecular data have so far included relatively few (less than 200) species, and none have included representatives from all described families and subfamilies [17-20,23,24]. This limited taxon sampling makes existing molecular phylogenies difficult to use for broadscale comparative studies, with some exceptions based on supertrees [10,11]. In addition, limited taxon sampling is potentially a serious issue for phylogenetic accuracy [25-28]. Thus, an analysis with extensive taxon sampling is critically important to test hypotheses based on molecular datasets with more limited sampling, and to provide a framework for comparative analyses. Despite the lack of a large-scale phylogeny across squamates, recent molecular studies have produced phylogenetic estimates for many of the major groups of squamates, including iguanian lizards [29-34], higherlevel snake groups [35-37], typhlopoid snakes [38,39], colubroid snakes [40-46], booid snakes [47,48], scincid lizards [49-52], gekkotan lizards [53-60], teiioid lizards [61-64], lacertid lizards [65-69], and amphisbaenians [70,71]. These studies have done an outstanding job of Page 2 of 53 clarifying the phylogeny and taxonomy of these groups, but many were limited in some ways by the number of characters and taxa that they sampled (and which were available at the time for sequencing). Here, we present a phylogenetic estimate for Squamata based on combining much of the existing sequence data for squamate reptiles, using the increasingly well-established supermatrix approach [41,72-77]. We present a new phylogenetic estimate including 4161 squamate species. The dataset includes up to 12896 bp per species from 12 genes (7 nuclear, 5 mitochondrial). We include species from all currently described families and subfamilies. In terms of species sampled, this is 5 times larger than any previous phylogeny for any one squamate group [30,41], 3 times larger than the largest supertree estimate [11], and 25 times larger than the largest molecular study of higher-level squamate relationships [20]. While we did not sequence any new taxa specifically for this project, much of the data in the combined matrix were generated in our labs or from our previous collaborative projects [16,19,20,34,36,37,41,44,78-82], including thousands of gene sequences from hundreds of species (>550 species; ~13% of the total). The supermatrix approach can provide a relatively comprehensive phylogeny, and uncover novel relationships not seen in any of the separate analyses in which the data were generated. Such novel relationships can be revealed via three primary mechanisms. First, different studies may have each sampled different species from a given group for the same genes, and combining these data may reveal novel relationships not apparent in the separate analyses. Second, different studies may have used different genetic markers for the same taxa, and combining these markers can dramatically increase character sampling, potentially revealing new relationships and providing stronger support for previous hypotheses. Third, even for clades that were previously studied using complete taxon sampling and multiple loci, novel relationships may be revealed by including these lineages with other related groups in a large-scale phylogeny. The estimated tree and branch-lengths should be useful for comparative studies of squamate biology. However, this phylogeny is based on a supermatrix with extensive missing data (mean = 81% per species). Some authors have suggested that matrices with missing cells may yield misleading estimates of topology, support, and branch lengths [83]. Nevertheless, most empirical and simulation studies have not found this to be the case, at least for topology and support [41,73,84,85]. Though fewer studies have examined the effects of missing data on branch lengths [44,86,87], these also suggest that missing data do not strongly impact estimates. Here, we test whether branch lengths for terminal taxa are related to their completeness. Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 In general, our results corroborate those of many recent molecular studies with regard to higher-level relationships, species-level relationships, and the monophyly, composition, and relationships of most families, subfamilies, and genera. However, our results differ from previous estimates for some groups, and reveal (or corroborate) numerous problems in the existing classification of squamates. We therefore provide a conservative, updated classification of extant squamates at the family and subfamily level based on the new phylogeny, while highlighting problematic taxonomy at the genus level, without making changes. The generic composition of all families and subfamilies under our revised taxonomy are provided in Appendix I. We note dozens of problems in the genus-level taxonomy suggested by our tree, but we acknowledge in advance that we do not provide a comprehensive review of the previous literature dealing with all these taxonomic issues (this would require a monographic treatment). Similarly, we do not attempt to fix these genus-level problems here, as most will require more extensive taxon (and potentially character) sampling to adequately resolve. Throughout the paper, we address only extant squamates. Squamata also includes numerous extinct species classified in both extant and extinct families, subfamilies, and genera. Relationships and classification of extinct squamates based on morphological data from fossils have been addressed by numerous authors (e.g. [14,15,19,22,88-93]). A classification based only on living taxa may create some problems for classifying fossil taxa, but these can be addressed in future studies that integrate molecular and fossil data [19,86]. Results Supermatrix phylogeny We generated the final tree (lnL = −2609551.07) using Maximum Likelihood (ML) in RAxMLv7.2.8. Support was assessed using the non-parametric ShimodairaHasegawa-Like (SHL) implementation of the approximate likelihood-ratio test (aLRT; see [94]). The tree and data matrix are available in NEXUS format in DataDryad repository 10.5061/dryad.82h0m and as Additional file 1: Data File S1. A skeletal representation of the tree (excluding several species which are incertae sedis) is shown in Figure 1. The full species-level phylogeny (minus the outgroup Sphenodon) is shown in Figures 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28. The analysis yields a generally well-supported phylogenetic estimate for squamates (i.e. 70% of nodes have SHL values >85, indicating they are strongly supported). There is no relationship between proportional completeness (bp of non-missing data in species / 12896 bp of complete data) and branch length (r = −0.29, P = 0.14) for terminal taxa, strongly suggesting that the estimated branch lengths are not consistently biased by missing data. Page 3 of 53 Higher-level relationships Our tree (Figure 1) is broadly congruent with most previous molecular studies of higher-level squamate phylogeny using both nuclear data and combined nuclear and mitochondrial data (e.g. [16-20]), providing important confirmation of previous molecular studies based on more limited taxon sampling. Specifically we support (Figure 1): (i) the placement of dibamids and gekkotans near the base of the tree (Figure 1A); (ii) a sister-group relationship between Scincoidea (scincids, cordylids, gerrhosaurids, and xantusiids; Figure 1B) and a clade (Episquamata; Figure 1C) containing the rest of the squamates excluding dibamids and gekkotans; (iii) Lacertoidea (lacertids, amphisbaenians, teiids, and gymnophthalmids; Figure 1D), and (iv) a clade (Toxicofera; Figure 1E) containing anguimorphs (Figure 1F), iguanians (Figure 1G), and snakes (Figure 1H) as the sister taxon to Lacertoidea. These relationships are strongly supported in general (Figure 1), but differ sharply from most trees based on morphological data [13-15,19,22,95]. Nevertheless, many clades found in previous morphological taxonomies and phylogenies are also present in this tree in some form, including Amphisbaenia, Anguimorpha, Gekkota, Iguania, Lacertoidea (but including amphisbaenians), Scincoidea, Serpentes, and many families and subfamilies. In contrast, the relationships among these groups differ strongly between molecular analyses [17-20] and morphological analyses [14,15]. Our results demonstrate that this incongruence is not explained by limited taxon sampling in the molecular data sets. In fact, our species-level sampling is far more extensive than in any morphological analyses (e.g. [14,15]), by an order of magnitude. We find that the basal squamate relationships are strongly supported in our tree. The family Dibamidae is the sister group to all other squamates, and Gekkota is the sister group to all squamates excluding Dibamidae (Figure 1), as in some previous studies (e.g. [16,18]). Other recent molecular analyses have also placed Dibamidae near the squamate root, but differed in placing it as either the sister taxon to all squamates excluding Gekkota [17], or the sister- group of Gekkota [19,20]. Our results also corroborate that the New World genus Anelytropsis is nested within the Old World genus Dibamus [96], but the associated branches are weakly supported (Figure 2). Gekkota Within Gekkota, we corroborate both earlier morphological [97] and recent molecular estimates [55,56,59,98] in supporting a clade containing the Australian radiation of "diplodactylid" geckos (Carphodactylidae and Diplodactylidae) and the snakelike pygopodids (Figures 1, 2). As in previous studies [55], Carphodactylidae is the weakly supported sister group to Pygopodidae, and this clade is the sister group of Diplodactylidae Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 4 of 53 Sphenodontidae Dibamidae 77 Carphodactylidae Pygopodidae Diplodactylidae Eublepharidae 100 Sphaerodactylidae 100 Phyllodactylidae Gekkonidae 100 Cricosaurinae Xantusiidae Xantusiinae 100 Lepidophyminae 99 100 Gerrhosaurinae Gerrhosauridae Zonosaurinae B 100 100 100 Platysaurinae Cordylidae Cordylinae 100 Acontiinae 95 Scincinae Scincidae 100 Lygosominae 94 Tupinambinae 54 Teiidae Teiinae Alopoglossinae 100 Bachiinae 84 Rhachisaurinae 98 Gymnophthalmidae Gymnophthalminae 99 100 Ecpleopinae 100 Cercosaurinae D Rhineuridae 99 Bipedidae 100 Blanidae 100 Cadeidae 84 100 Trogonophiidae Amphisbaenidae 100 100 Gallotiinae Lacertidae Lacertinae Xenosauridae 100 Helodermatidae Anniellidae Diploglossinae F 95 100 Anguinae Anguidae 90 100 Gerrhonotinae 100 C Shinisauridae 100 Lanthanotidae 94 Varanidae 100 100 Brookesiinae 79 Chamaeleonidae Chamaeleoninae Uromastycinae 100 Leiolepidinae 100 Hydrosaurinae Agamidae 96 Amphibolurinae 100 Agaminae 100 G Draconinae 100 Tropiduridae 100 Iguanidae Leiocephalidae Crotaphytidae 72 87 Phrynosomatidae 54 96 E Polychrotidae 99 Hoplocercidae 81 Opluridae 99 Enyaliinae 63 Leiosauridae Leiosaurinae 95 100 Liolaemidae Corytophanidae Dactyloidae 99 Anomalepididae Leptotyphlopidae 90 Gerrhopilidae H 100 Xenotyphlopidae 100 Typhlopidae 83 Aniliidae 98 Tropidophiidae Xenophiidae Bolyeriidae Sanziniinae 100 100 Calabariidae Ungaliophiinae Boidae 69 Candoiinae 99 87 97 Erycinae 88 83 Boinae Anomochilidae 65 Cylindrophiidae 100 Uropeltidae 89 Xenopeltidae Loxocemidae 98 100 Pythonidae Acrochordidae 95 Xenodermatidae Pareatidae Viperinae 100 100 Azemiopinae Viperidae Crotalinae 100 100 Homalopsidae Prosymninae 95 Psammophiinae 58 95 95 Atractaspidinae 100 Aparallactinae 96 Lamprophiidae Pseudaspidinae Lamprophiinae 90 Pseudoxyrhophiinae 100 Elapidae Calamariinae 97 Pseudoxenodontinae Sibynophiinae Colubridae 100 74 Grayiinae 71 Colubrinae 68 Natricinae 0.2 subst./site Dipsadinae A Squamata A) Gekkota B) Scincoidea C) Episquamata D) Lacertoidea E) Toxicofera F) Anguimorpha G) Iguania H) Serpentes 100 Figure 1 Higher-level squamate phylogeny. Skeletal representation of the 4161-species tree from maximum-likelihood analysis of 12 genes, with tips representing families and subfamilies (following our taxonomic revision; species considered incertae sedis are not shown). Numbers at nodes are SHL values greater than 50%. The full tree is presented in Figures 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28. Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 A Figure 2 (See legend on next page.) Page 5 of 53 Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 6 of 53 (See figure on previous page.) Figure 2 Species-level squamate phylogeny. Large-scale maximum likelihood estimate of squamate phylogeny, containing 4161 species. Numbers at nodes are SHL values greater than 50%. A skeletal version of this tree is presented in Figure 1. Bold italic letters indicate figure panels (A-AA). Within panels, branch lengths are proportional to expected substitutions per site, but the relative scale differs between panels. (Figures 1, 2). We recover clades within the former Gekkonidae that correspond to the strongly supported families Eublepharidae, Sphaerodactylidae, Phyllodactylidae, and Gekkonidae as in previous studies, and similar relationships among these groups [55-57,59,60,98-100]. Within Gekkota, we find evidence for non-monophyly of many genera. Many relationships among the New Caledonian diplodactylids are weakly supported (Figure 2), and there is apparent non-monophyly of the genera Rhacodactylus, Bavayia, and Eurydactylodes with respect to each other and Oedodera, Dierogekko, Paniegekko, Correlophus, and Mniarogekko [101]. In the Australian diplodactylids, Strophurus taenicauda is strongly supported as belonging to a clade that is only distantly related to the other sampled Strophurus species (Figure 2). The two species of the North African sphaerodactylid genus Saurodactylus are divided between the two major sphaerodactylid clades (Figure 3), but the associated branches are weakly supported. The South American phyllodactylid genus Homonota is strongly supported as being paraphyletic with respect to Phyllodactylus (Figure 3). A number of gekkonid genera (Figure 4) also appear to be non-monophyletic, including the Asian genera Cnemaspis (sampled species divided into two non-sister clades), Lepidodactylus (with respect to Pseudogekko and some Luperosaurus), Gekko (with respect to Ptychozoon and Lu. iskandari), Luperosaurus (with respect to Lepidodactylus and Gekko), Mediodactylus (with respect to Pseudoceramodactylus, Tropiocolotes, Stenodactylus, Cyrtopodion, Bunopus, Crossobamon, and Agamura), and Bunopus (with respect to Crossobamon), and the African Afrogecko (with respect to Afroedura, Christinus, Cryptactites, and Matoatoa), Afroedura (with respect to Afrogecko, Blaesodactylus, Christinus, Geckolepis, Pachydactylus, Rhoptropus, and numerous other genera), Chondrodactylus (with respect to Pachydactylus laevigatus), and Pachydactylus (with respect to Chondrodactylus and Colopus). Many of these taxonomic problems in gekkotan families have been identified in previous studies (e.g. [59,99,102]), and extensive changes will likely be required to fix them. Scincoidea We strongly support (SHL = 100; Figures 1, 5, 6, 7, 8, 9, 10) the monophyly of Scincoidea (Scincidae, Xantusiidae, Gerrhosauridae, and Cordylidae), as in other recent studies [16-20]. All four families are strongly supported (Figures 5, 6, 7, 8, 9, 10). A similar clade is also re- cognized in morphological phylogenies [14], though without Xantusiidae in some [13]. Within the New World family Xantusiidae, we corroborate previous analyses [103,104] that found strong support for a sister-group relationship between Xantusia and Lepidophyma, excluding Cricosaura (Figure 5). These relationships support the subfamily Cricosaurinae for Cricosaura [105]. We also recognize Xantusiinae for the North American genus Xantusia and Lepidophyminae for the Central American genus Lepidophyma [106,107]. Within the African and Madagascan family Gerrhosauridae (Figure 5), the genus Gerrhosaurus is weakly supported as being paraphyletic with respect to the clade comprising Tetradactylus + Cordylosaurus, with G. major placed as the sister group to all other gerrhosaurids. Within Cordylidae (Figure 5), we use the generic taxonomy from a recent phylogenetic analysis and reclassification based on multiple nuclear and mitochondrial genes [108]. This classification broke up the nonmonophyletic Cordylus [109] into several smaller genera, and we corroborate the non-monophyly of the former Cordylus and support the monophyly of the newly recognized genera (Figure 5). We support the distinctiveness of Platysaurus (Figure 5) and recognition of the subfamily Platysaurinae [108]. We strong support (SHL = 100) for the monophyly of Scincidae (Figure 6) as in previous studies (e.g. [20,50,51]). We strongly support the basal placement of the monophyletic subfamily Acontiinae (Figure 6), as found in some previous studies (e.g. [20,51]) but not others (e.g. [50]). Similar to earlier studies, we find that the subfamily Scincinae (sensu [110]) is non-monophyletic, as Feylininae is nested within Scincinae (also found in [20,50,51,111]). Based on these results, synonymizing Feylininae with Scincinae produces a monophyletic Scincinae (SHL = 97), which is then sister to a monophyletic Lygosominae (SHL = 100 excluding Ateuchosaurus; see below) with 94% SHL support (Figures 6, 7, 8, 9, 10). This yields a new classification in which all three subfamilies (Acontiinae, Lygosominae, Scincinae) are strongly supported. Importantly, these definitions approxi \mate the traditional content of the three subfamilies [50,110], except for recognition of Feylininae. We note that a recent revision of the New World genus Mabuya introduced a nontraditional family-level classification for Scincidae [112]. These authors divided Scincidae into seven families: Acontiidae, Egerniidae, Eugongylidae, Lygosomidae, Mabuyidae, Scincidae and Sphenomorphidae. However, there was no phylogenetic Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 7 of 53 79 Eublepharidae 100 100 100 97 60 100 75 100 78 99 83 100 Sphaerodactylidae Aeluroscalabotes felinus Coleonyx brevis Coleonyx variegatus Coleonyx mitratus Coleonyx elegans 100 100 Eublepharis macularius Eublepharis turcmenicus Holodactylus africanus Hemitheconyx caudicinctus 100 Hemitheconyx taylori 100 Goniurosaurus kuroiwae Goniurosaurus lichtenfelderi Goniurosaurus catbaensis 100 Goniurosaurus luii 96 Goniurosaurus araneus 90 Pristurus celerrimus 100 Pristurus insignis 100 Pristurus sokotranus Pristurus guichardi 76 Pristurus abdelkuri 92 100 Pristurus flavipunctatus Pristurus rupestris Pristurus minimus 100 Pristurus carteri 63 98 Pristurus crucifer 85 Pristurus somalicus 100 Quedenfeldtia trachyblepharus Quedenfeldtia moerens Aristelliger lar 100 Aristelliger praesignis Aristelliger georgeensis 91 Saurodactylus fasciatus Euleptes europaea Teratoscincus microlepis Teratoscincus scincus 100 Teratoscincus przewalskii 97 Teratoscincus roborowskii 98 Saurodactylus mauritanicus Chatogekko amazonicus 100 Lepidoblepharis xanthostigma Lepidoblepharis festae 97 Gonatodes eladioi Gonatodes caudiscutatus 89 Gonatodes daudini 100 Gonatodes albogularis 96 Gonatodes petersi 100 Gonatodes vittatus Gonatodes infernalis 98 Gonatodes hasemani Gonatodes annularis 70 Gonatodes superciliaris 60 Gonatodes alexandermendesi 100 Gonatodes purpurogularis 60 Gonatodes taniae 100 Gonatodes falconensis 95 Gonatodes humeralis 97 Gonatodes antillensis 100 Gonatodes concinnatus 93 89 Gonatodes seigliei 100 Gonatodes ceciliae 99 Gonatodes ocellatus Coleodactylus septentrionalis Coleodactylus brachystoma 100 Coleodactylus meridionalis 99 Coleodactylus natalensis 100 100 Pseudogonatodes manessi 96 Pseudogonatodes lunulatus Pseudogonatodes guianensis Sphaerodactylus fantasticus Sphaerodactylus sputator 98 87 Sphaerodactylus elegantulus Sphaerodactylus sabanus Sphaerodactylus parvus 81 Sphaerodactylus microlepis Sphaerodactylus vincenti 82 100 100 Sphaerodactylus kirbyi Sphaerodactylus schwartzi Sphaerodactylus ramsdeni 84 84 Sphaerodactylus cricoderus Sphaerodactylus richardi 83 Sphaerodactylus oliveri 100 91 Sphaerodactylus molei 84 Sphaerodactylus glaucus Sphaerodactylus thompsoni 81 69 Sphaerodactylus cinereus Sphaerodactylus torrei Sphaerodactylus intermedius 100 100 Sphaerodactylus nigropunctatus 93 Sphaerodactylus copei 83 Sphaerodactylus leucaster Sphaerodactylus elegans Sphaerodactylus shrevei 99 85 Sphaerodactylus cryphius Sphaerodactylus darlingtoni 90 Sphaerodactylus notatus Sphaerodactylus altavelensis 52 Sphaerodactylus roosevelti 85 Sphaerodactylus argus Sphaerodactylus macrolepis 93 Sphaerodactylus armstrongi 84 Sphaerodactylus townsendi 83 Sphaerodactylus goniorhynchus 66 79 Sphaerodactylus semasiops Sphaerodactylus klauberi Sphaerodactylus gaigeae 94 Sphaerodactylus ocoae 99 Sphaerodactylus nicholsi 100 Thecadactylus solimoensis Thecadactylus rapicauda Haemodracon riebeckii Asaccus platyrhynchus Ptyodactylus ragazzii 100 Ptyodactylus oudrii 100 Ptyodactylus hasselquistii Ptyodactylus guttatus Homonota gaudichaudii Homonota fasciata Homonota underwoodi 100 Homonota borellii 85 Homonota darwinii Homonota andicola 92 Phyllodactylus wirshingi Phyllodactylus reissii 100 Phyllodactylus tuberculosus 86 Phyllodactylus lanei 65 Phyllodactylus bordai 100 97 Phyllodactylus xanti Phyllodactylus unctus 99 100 Phyllodactylus bugastrolepis 97 Phyllodactylus nocticolus 100 Phyllodactylus paucituberculatus Phyllodactylus delcampoi 67 Phyllodactylus duellmani 75 Phyllodactylus davisi 96 57 Phyllodactylus homolepidurus Phyllopezus periosus Phyllopezus pollicaris 100 Phyllopezus lutzae 90 92 Phyllopezus maranjonensis Tarentola americana Tarentola boehmei 100 Tarentola deserti 100 Tarentola mauritanica 99 Tarentola angustimentalis Tarentola neglecta 87 100 Tarentola mindiae 99 Tarentola boettgeri 100 Tarentola ephippiata 93 Tarentola annularis Tarentola gomerensis 76 Tarentola delalandii 91 Tarentola chazaliae 62 Tarentola darwini Tarentola rudis 100 99 Tarentola caboverdiana 73 Tarentola gigas 100 100 79 82 87 100 Phyllodactylidae 98 65 93 100 100 100 92 73 B Figure 3 Species-level squamate phylogeny continued (B). C Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Lepidodactylus novaeguineae Perochirus ateles Pseudogekko smaragdinus Urocotyledon inexpectata Ebenavia inunguis 93 Pseudogekko compressicorpus Paroedura masobe 83 Lepidodactylus orientalis Paroedura gracilis Luperosaurus macgregori 100 100 Paroedura homalorhina 99 98 Luperosaurus cumingii Paroedura oviceps Luperosaurus joloensis 79 Paroedura karstophila 73 100 Lepidodactylus lugubris Paroedura lohatsara 100 100 100 91 Lepidodactylus moestus Paroedura stumpffi Gekko smithii 100 Paroedura sanctijohannis 85 Gekko gecko Paroedura picta 99 Gekko chinensis Paroedura androyensis 100 100 Paroedura vazimba Gekko japonicus 92 99 Paroedura tanjaka Gekko hokouensis 61 Paroedura bastardi 100 95 Gekko auriverrucosus 98 100 Ailuronyx tachyscopaeus Gekko swinhonis 54 Ailuronyx seychellensis Gekko athymus 100 Ailuronyx trachygaster Gekko monarchus 100 Calodactylodes illingworthorum Gekko mindorensis Calodactylodes aureus 100 100 98 Gekko romblon Ptenopus carpi 99 Gekko crombota Narudasia festiva 65 80 Cnemaspis uzungwae Gekko porosus 100 Cnemaspis dickersonae Ptychozoon rhacophorus 53 100 89 69 Cnemaspis africana Ptychozoon kuhli 87 Uroplatus guentheri 64 Ptychozoon lionotum 92 95 Uroplatus malahelo Luperosaurus iskandari Uroplatus malama 100 Gekko vittatus 100 Uroplatus ebenaui 97 Gekko petricolus Uroplatus phantasticus 94 100 85 Gekko badenii Uroplatus alluaudi 96 Gekko grossmanni 50 Uroplatus pietschmanni 100 Dixonius melanostictus Uroplatus lineatus 100 Uroplatus sikorae 100 Dixonius vietnamensis 100 100 Uroplatus henkeli 77 Dixonius siamensis 100 Uroplatus giganteus 100 Heteronotia planiceps 100 Uroplatus fimbriatus 100 Heteronotia binoei 100 Paragehyra gabriellae Heteronotia spelea 56 Christinus marmoratus 97 Nactus acutus Afrogecko swartbergensis Nactus eboracensis Cryptactites peringueyi 100 100 Nactus vankampeni Matoatoa brevipes 100 Nactus galgajuga 100 Afrogecko porphyreus 83 52 Nactus cheverti Afroedura pondolia 100 52 Afroedura karroica Nactus multicarinatus 100 98 79 Geckolepis typica Nactus pelagicus Geckolepis maculata 100 Hemiphyllodactylus typus Homopholis fasciata 99 89 Hemiphyllodactylus yunnanensis 100 100 Homopholis walbergii 93 Hemiphyllodactylus aurantiacus 85 Homopho lis mulleri Gehyra fehlmanni 100 100 Blaesodactylus boivini Gehyra mutilata Blaesodactylus antongilensis 99 100 98 Gehyra lacerata 100 Blaesodactylus sakalava 97 Gehyra brevipalmata Goggia lineata 100 Rhoptropus afer Gehyra baliola 100 Rhoptropus bradfieldi Gehyra barea 84 99 Rhoptropus boultoni Gehyra marginata 100 59 99 Rhoptropus biporosus Gehyra oceanica 98 91 Rhoptropus barnardi 98 Gehyra membranacruralis 96 86 Elasmodactylus tetensis Gehyra dubia 100 Elasmodactylus tuberculosus 100 Gehyra catenata Chondrodactylus angulifer 100 Gehyra pamela Pachydactylus laevigatus 100 Gehyra borroloola Chondrodactylus turneri 55 100 96 97 Gehyra robusta Chondrodactylus fitzsimonsi 100 86 70 Chondrodactylus bibronii Gehyra koira Pachydactylus robertsi 100 Gehyra occidentalis 93 100 Colopus wahlbergii Gehyra australis Colopus kochii Gehyra xenopus 98 Pachydactylus haackei Gehyra nana Pachydactylus kladaroderma Gehyra purpurascens 98 89 Pachydactylus namaquensis 100 Pachydactylus scutatus 98 68 100 Gehyra variegata Gehyra punctata 74 100 Pachydactylus parascutatus Gehyra pilbara Pachydactylus reconditus 98 70 Gehyra montium Pachydactylus gaiasensis 95 92 Pachydactylus oreophilus 90 Gehyra minuta 100 91 Pachydactylus bicolor Alsophylax pipiens Pachydactylus caraculicus Tropiocolotes helenae Pachydactylus sansteynae 65 100 63 Cnemaspis limi Pachydactylus scherzi 86 Cnemaspis kendallii Pachydactylus punctatus 96 100 Mediodactylus spinicaudum 85 Pachydactylus rugosus 100 Mediodactylus russowii 99 98 Pachydactylus formosus Pseudoceramodactylus khobarensis Pachydactylus barnardi 95 Tropiocolotes tripolitanus Pachydactylus labialis 84 96 Pachydactylus geitje Stenodactylus arabicus Pachydactylus maculatus 92 Stenodactylus petrii 52 Pachydactylus oculatus 93 100 Stenodactylus leptocosymbotus Pachydactylus purcelli Stenodactylus doriae 96 100 Pachydactylus waterbergensis 61 100 Stenodactylus yemenensis Pachydactylus tsodiloensis 100 97 Stenodactylus sthenodactylus 85 Pachydactylus fasciatus Mediodactylus kotschyi 98 Pachydactylus carinatus 85 Mediodactylus sagittiferum Pachydactylus griffini 99 Mediodactylus heterocercum Pachydactylus serval 68 69 Mediodactylus heteropholis Pachydactylus weberi 99 74 Pachydactylus monicae Bunopus tuberculatus 100 75 Pachydactylus mclachlani 69 Crossobamon orientalis Pachydactylus mariquensis Bunopus crassicauda 86 99 Pachydactylus austeni Agamura persica 95 Pachydactylus rangei Cyrtopodion sistanensis 100 Pachydactylus vanzyli Cyrtopodion scabrum 99 Pachydactylus montanus Cyrtopodion longipes Pachydactylus tigrinus 79 Cyrtopodion caspium 100 100 Pachydactylus oshaughnessyi Cyrtopodion agamuroides Pachydactylus capensis 72 Pachydactylus vansoni Cyrtopodion gastrophole 99 100 100 Pachydactylus affinis Cyrtodactylus oldhami Cnemaspis podihuna 87 100 Cyrtodactylus ayeyarwadyensis Cnemaspis kandiana 100 Cyrtodactylus angularis 100 99 Cnemaspis tropidogaster Cyrtodactylus jarujini Rhoptropella ocellata Cyrtodactylus triedrus Lygodactylus expectatus 88 Cyrtodactylus marmoratus Lygodactylus rarus 92 Cyrtodactylus irregularis Lygodactylus madagascariensis 99 71 Cyrtodactylus consobrinus 100 Lygodactylus miops 98 Cyrtodactylus annulatus 92 Lygodactylus guibei 52 Lygodactylus tolampyae Cyrtodactylus philippinicus 97 100 92 Lygodactylus heterurus Cyrtodactylus agusanensis 98 100 100 Lygodactylus verticillatus Cyrtodactylus intermedius Lygodactylus blancae 81 Cyrtodactylus pulchellus Lygodactylus arnoulti 79 91 90 Cyrtodactylus sermowaiensis 85 Lygodactylus pauliani 94 Cyrtodactylus loriae Lygodactylus gravis 77 Cyrtodactylus novaeguineae 81 Lygodactylus montanus 99 82 Cyrtodactylus tuberculatus Lygodactylus tuberosus 96 98 Cyrtodactylus klugei Lygodactylus mirabilis 73 97 Cyrtodactylus robustus 98 Lygodactylus pictus Lygodactylus lawrencei Cyrtodactylus tripartitus 98 Lygodactylus stevensoni Cyrtodactylus epiroticus 89 98 68 Lygodactylus capensis Cyrtodactylus louisiadensis 93 99 84 Lygodactylus bradfieldi Hemidactylus bowringii 100 Lygodactylus klugei Hemidactylus garnotii 100 Lygodactylus conraui Hemidactylus karenorum 100 97 Lygodactylus thomensis Hemidactylus platyurus Lygodactylus angularis 78 Hemidactylus fasciatus Lygodactylus gutturalis 67 100 Hemidactylus aaronbaueri Lygodactylus chobiensis 94 93 Lygodactylus williamsi Hemidactylus giganteus 81 94 Lygodactylus picturatus Hemidactylus depressus 68 100 Lygodactylus luteopicturatus Hemidactylus triedrus 89 97 Lygodactylus kimhowelli Hemidac tylus prashadi 93 88 Lygodactylus keniensis Hemidactylus maculatu s 100 76 92 93 Phelsuma vanheygeni 100 Hemidactylus leschenaultii Phelsuma astriata 100 Hemidactylus flaviviridis 100 Phelsuma sundbergi Hemidactylus frenatus Phelsuma guttata Hemidactylus brookii Phelsuma madagascariensis 100 Hemidactylus sataraensis Phelsuma abbotti 100 100 Phelsuma parkeri Hemidactylus imbricatus 100 99 87 Phelsuma seippi Hemidactylus albofasciatus 56 Phelsuma barbouri Hemidactylus reticulatus 100 100 Phelsuma pronki Hemidactylus gracilis 96 97 Phelsuma breviceps Hemidactylus angulatus Phelsuma mutabilis 85 Hemidactylus haitianus 100 Phelsuma andamanense 92 57 Hemidactylus mabouia Phelsuma standingi 82 Phelsuma edwardnewtoni 100 Hemidactylus mercatorius 94 Hemidactylus longicephalus Phelsuma gigas Hemidactylus platycephalus guentheri 100 99 99 Phelsuma 97 Phelsuma borbonica Hemidac tylus greeffii 95 100 Phelsuma cepediana Hemidactylus bra silianus 100 Phelsuma guimbeaui Hemidactylus bouvieri 96 Phelsuma ornata 100 99 Hemidactylus palaichthus 95 100 Phelsuma inexpectata 55 97 Hemidactylus agrius Phelsuma nigristriata Hemidactylus modestus 96 Phelsuma modesta 100 98 Hemidactylus citernii Phelsuma dubia Hemidactylus foudaii 100 Phelsuma ravenala Hemidactylus pumilio 98 Phelsuma flavigularis 98 Phelsuma hielscheri Hemidactylus dracaenacolus 94 Phelsuma berghofi Hemidactylus granti 100 99 100 Phelsuma malamakibo Hemidactylus persicus 97 Phelsuma serraticauda 82 Hemidactylus yerburii 95 Phelsuma laticauda Hemidactylus robustus 95 91 Phelsuma robertmertensi Hemidactylus turcicus 99 Phelsuma klemmeri 99 96 Hemidactylus lemurinus 91 Phelsuma antanosy Hemidactylus mindiae 87 Phelsuma quadriocellata 96 Hemidactylus macropholis Phelsuma pusilla 99 Hemidactylus oxyrhinus Phelsuma comorensis 100 66 Phelsuma lineata Hemidactylus forbesii 57 97 94 Phelsuma kely 98 Hemidactylus homoeolepis 100 (i) Page 8 of 53 100 (ii) 100 Gekkonidae (ii) (i) C Figure 4 Species-level squamate phylogeny continued (C). Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 9 of 53 Cricosaura typica Xantusia gracilis Xantusia henshawi Xantusia bolsonae 100 Xantusia sanchezi 100 Xantusia riversiana 84 97 Xantusia arizonae 92 Xantusia vigilis Xantusia bezyi 100 100 Xantusia wigginsi 66 Lepidophyma mayae Lepidophyma tuxtlae 100 100 Lepidophyma lipetzi Lepidophyma flavimaculatum Lepidophyminae 100 Lepidophyma reticulatum 100 Lepidophyma pajapanensis Lepidophyma occulor 94 Lepidophyma micropholis 87 Lepidophyma sylvaticum 100 Lepidophyma gaigeae 95 Lepidophyma lineri Lepidophyma smithii Lepidophyma cuicateca 95 Lepidophyma lowei 94 Lepidophyma radula 100 Lepidophyma dontomasi 100 Gerrhosaurus major 100 Cordylosaurus subtessellatus Gerrhosaurinae 95 Tetradactylus seps Tetradactylus africanus 98 69 Tetradactylus tetradactylus Gerrhosaurus validus Gerrhosaurus skoogi 79 Gerrhosaurus typicus Gerrhosauridae Gerrhosaurus nigrolineatus 91 100 Gerrhosaurus multilineatus 100 Gerrhosaurus flavigularis 76 100 Tracheloptychus madagascariensis Tracheloptychus petersi 100 Zonosaurus haraldmeieri 100 Zonosaurus madagascariensis Zonosaurinae Zonosaurus ornatus 100 Zonosaurus trilineatus Zonosaurus quadrilineatus 91 Zonosaurus karsteni 100 Zonosaurus anelanelany 100 Zonosaurus laticaudatus 96 Zonosaurus boettgeri 100 Zonosaurus tsingy Zonosaurus brygooi 66 73 Zonosaurus subunicolor 82 Zonosaurus bemaraha 89 Zonosaurus aeneus 87 Zonosaurus rufipes Platysaurus pungweensis Platysaurinae Platysaurus mitchelli 92 Platysaurus broadleyi 100 Platysaurus capensis Platysaurus intermedius 91 Platysaurus minor Platysaurus monotropis 100 Ouroborus cataphractus 100 Cordylidae Karusasaurus jordani Karusasaurus polyzonus 99 Namazonurus campbelli Namazonurus pustulatus 100 100 Namazonurus namaquensis Namazonurus lawrenci Cordylinae 100 Namazonurus peersi 94 Smaug warreni Smaug giganteus 100 Chamaesaura aenea 55 Chamaesaura anguina Pseudocordylus langi 93 Pseudocordylus microlepidotus Pseudocordylus spinosus 100 Pseudocordylus melanotus 99 95 Ninurta coeruleopunctatus 86 Hemicordylus nebulosus 100 Hemicordylus capensis 95 Cordylus tropidosternum Cordylus meculae 99 Cordylus vittifer 96 81 88 Cordylus ukingensis Cordylus beraduccii 82 Cordylus jonesii 83 Cordylus rhodesianus 99 Cordylus macropholis 92 Cordylus imkeae 83 Cordylus aridus 100 Cordylus minor 100 84 Cordylus niger Cordylus mclachlani 85 Cordylus oelofseni Cordylus tasmani 86 100 Cordylus cordylus 100 Cricosaurinae Xantusiinae 100 Xantusiidae 99 D Figure 5 Species-level squamate phylogeny continued (D). Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 10 of 53 89 Acontiinae 95 99 100 Typhlosaurus braini Typhlosaurus meyeri Typhlosaurus caecus Typhlosaurus vermis 100 Typhlosaurus lomiae Acontias gariepensis Acontias lineatus Acontias litoralis 100 Acontias kgalagadi Acontias meleagris Acontias percivali Acontias rieppeli Acontias breviceps 98 Acontias gracilicauda 92 Acontias plumbeus Acontias poecilus 100 Mesoscincus schwartzei 98 91 Mesoscincus managuae Ophiomorus punctatissimus Ophiomorus latastii 99 Brachymeles apus Brachymeles miriamae 99 Brachymeles tridactylus 100 Brachymeles bonitae 94 Brachymeles minimus 94 Brachymeles cebuensis 95 Brachymeles samarensis Brachymeles talinis 83 Brachymeles elerae 88 Brachymeles schadenbergi Brachymeles boulengeri 85 Brachymeles bicolor 85 73 Brachymeles gracilis 85 Brachymeles pathfinderi Plestiodon tamdaoensis 100 Plestiodon kishinouyei 100 Plestiodon chinensis Plestiodon quadrilineatus 98 Plestiodon tunganus Plestiodon capito 100 100 86 Plestiodon barbouri Plestiodon japonicus Plestiodon latiscutatus 97 70 Plestiodon elegans 93 Plestiodon marginatus 100 Plestiodon stimpsonii Plestiodon reynoldsi Plestiodon egregius 100 97 88 Plestiodon anthracinus 74 Plestiodon inexpectatus Plestiodon laticeps 56 97 Plestiodon tetragrammus 100 Plestiodon callicephalus 74 Plestiodon obsoletus 76 Plestiodon fasciatus 71 100 Plestiodon multivirgatus 98 86 Plestiodon septentrionalis Plestiodon longirostris 92 Plestiodon gilberti Plestiodon lagunensis 100 Plestiodon skiltonianus Plestiodon parviauriculatus Plestiodon sumichrasti 100 91 Plestiodon lynxe Plestiodon ochoterenae 73 73 Plestiodon parvulus 76 Plestiodon copei Plestiodon brevirostris Plestiodon dugesii 98 Eurylepis taeniolatus Eumeces schneideri 77 Scincopus fasciatus 100 Eumeces algeriensis 100 Scincus scincus 100 Scincus mitranus Pamelaescincus gardineri 99 Janetaescincus veseyfitzgeraldi Janetaescincus braueri 100 Gongylomorphus bojerii Chalcides mauritanicus 55 81 92 Chalcides minutus 57 Chalcides guentheri Chalcides chalcides 100 Chalcides pseudostriatus 86 Chalcides striatus 75 Chalcides ocellatus 74 100 Chalcides sepsoides Chalcides colosii 91 Chalcides bedriagai 100 74 Chalcides boulengeri Chalcides parallelus 87 88 Chalcides lanzai 99 Chalcides sexlineatus 98 99 Chalcides coeruleopunctatus Chalcides viridanus Chalcides sphenopsiformis 100 Chalcides mionecton Chalcides manueli 94 Chalcides polylepis 95 96 Chalcides montanus Sepsina angolensis 97 100 97 Typhlacontias brevipes Typhlacontias punctatissimus 100 Feylinia grandisquamis 100 Feylinia polylepis 96 Feylinia currori 98 93 Melanoseps occidentalis 96 100 Melanoseps ater Melanoseps loveridgei Hakaria simonyi Proscelotes eggeli Scelotes caffer 80 Scelotes anguineus 89 100 Scelotes mirus Scelotes arenicolus 87 99 Scelotes bipes Scelotes sexlineatus 100 97 Scelotes gronovii Scelotes montispectus 75 92 Scelotes kasneri 94 Paracontias holomelas 100 Paracontias brocchii Paracontias manify 60 100 Paracontias hildebrandti 69 Paracontias rothschildi Madascincus melanopleura 89 Pseudoacontias menamainty 52 Madascincus igneocaudatus Madascincus mouroundavae 97 Madascincus nanus 64 100 Madascincus stumpffi 100 Madascincus polleni 87 Madascincus intermedius 100 Amphiglossus melanurus 90 Amphiglossus ornaticeps 100 Amphiglossus mandokava Amphiglossus tanysoma 100 Pygomeles braconnieri 100 Androngo trivittatus Amphiglossus tsaratananensis 93 Amphiglossus reticulatus 85 86 Amphiglossus astrolabi Voeltzkowia fierinensis 93 Voeltzkowia lineata 100 95 Voeltzkowia rubrocaudata 24 Amphiglossus splendidus Amphiglossus anosyensis 80 Amphiglossus macrocercus 70 Amphiglossus punctatus 90 96 Amphiglossus frontoparietalis 96 94 Scincidae 100 Scincinae 94 F-I E Figure 6 Species-level squamate phylogeny continued (E). 98 Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 11 of 53 Ateuchosaurus pellopleurus Asymblepharus alaicus Ablepharus pannonicus Sphenomorphus praesignis 81 Sphenomorphus si mus Tropidophorus berdmorei 98 60 Tropidophorus matsuii 100 Tropidophorus latiscutatus Tropidophorus noggei 90 99 Tropidophorus murphyi Tropidophorus hainanus 100 89 98 Tropidophorus baviensis Tropidophorus sinicus Tropidophorus robinsoni 98 Tropidophorus thai Tropidophorus cocincinensis 83 89 Tropidophorus microlepis Tropidophorus grayi 97 95 Tropidophorus baconi 100 94 Tropidophorus beccarii Tropidophorus brookei 100 Tropidophorus partelloi 95 Tropidophorus misaminius Lipinia vittigera 86 Isopachys anguinoides Sphenomorphus melanopogon 77 98 Sphenomorphus jobiensis Sphenomorphus muelleri Tytthoscincus aesculeticola 100 Tytthoscincus parvus Tytthoscincus hallieri 100 92 Tytthoscincus atrigularis 94 Sphenomorphus concinnatus 99 95 Sphenomorphus scutatus 100 Sphenomorphus solomonis 100 Sphenomorphus fasciatus Sphenomorphus leptofasciatus 100 87 Sphenomorphus cranei 90 76 Sphenomorphus maindroni 93 Otosaurus cumingi Pinoyscincus mindanen sis 100 Pinoyscincus jagori 96 Pinoyscincus coxi 100 80 Pinoyscincus abdictus 100 100 Pinoyscincus llanosi Sphenomorphus diwata Sphenomorphus acutus 89 Parvoscincus steerei Parvoscincus decipiens 100 Parvoscincus leucospilos Parvoscincus tagapayo 100 Parvoscincus sisoni 76 Parvoscincus beyeri 97 100 Parvoscincus laterimaculatus Parvoscincus luzonense 99 Parvoscincus kitangladensis 68 83 Parvoscincus lawtoni Larutia seribuatensis Sphenomorphus maculatus Sphenomorphus indicus 100 100 Sphenomorphus multisquamatus 91 Sphenomorphus variegatus 100 Sphenomorphus cyanolaemus 100 Sphenomorphus sabanus Scincella reevesii 65 Asymblepharus sikimmensis Scincella lateralis 96 Scincella gemmingeri 93 Scincella cherriei 54 99 Scincella assatus 99 99 Sphenomorphus buenloicus Prasinohaema virens Insulasaurus arborens 100 98 Insulasaurus wrighti 80 Insulasaurus victoria 99 Lipinia pulchella Lipinia noctua 94 100 Papuascincus stanleyanus G 100 Lygosominae F Lygosominae cont. H-I Figure 7 Species-level squamate phylogeny continued (F). Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 12 of 53 Eulamprus frerei Nangura spinosa Calyptotis lepidorostrum Calyptotis scutirostrum Calyptotis ruficauda 77 97 Gnypetoscincus queenslandiae 98 Eulamprus amplus Eulamprus tenuis 78 Eulamprus tigrinus 96 Eulamprus martini Eulamprus sokosoma 100 88 Eulamprus brachyosoma 80 Eulamprus luteilateralis 85 Eulamprus tryoni Eulamprus murrayi 83 77 Coggeria naufragus 91 Coeranoscincus frontalis Ophioscincus ophioscincus 95 Saiphos equalis Coeranoscincus reticulatus 95 Ophioscincus truncatus Anomalopus swansoni Anomalopus mackayi 100 Anomalopus verreauxi 100 Anomalopus leuckartii Eremiascincus fasciolatus Eremiascincus pardal is 100 Eremiascincus richardsonii 97 Eremiascincus douglasi 91 62 88 Eremiascincus isolepis Hemiergis initialis 100 100 Hemiergis peronii 100 Hemiergis quadrilineatum 70 Hemiergis gracilipes Hemiergis millewae 82 Hemiergis decresiensis 60 Glaphyromorphus punctulatus Glaphyromorphus mjobergi 95 Glaphyromorphus fuscicaudis 93 Glaphyromorphus pumilus Glaphyromorphus cracens 99 Glaphyromorphus darwiniensis 78 Eulamprus quoyii 100 Eulamprus leuraensis 93 Eulamprus kosciusk oi Eulamprus heatwolei 82 Eulamprus tympanum 87 Notoscincus ornatus Ctenotus labillardieri 76 Ctenotus brooksi 99 95 Ctenotus rubicundus Ctenotus nasutus Ctenotus pantherinus 100 Ctenotus strauchii 95 Ctenotus youngsoni 81 Ctenotus schomburgkii Ctenotus calurus 85 Ctenotus rawlinsoni 84 Ctenotus fallens Ctenotus saxatilis 67 Ctenotus inornatus 85 Ctenotus spaldingi Ctenotus robustus 99 Ctenotus taeniolatus 76 Ctenotus rutilans 89 55 Ctenotus uber Ctenotus australis Ctenotus leae 88 95 Ctenotus leonhardii Ctenotus quattuordecimlineatus 100 Ctenotus serventyi 100 Ctenotus greeri 83 Ctenotus tanamiensis 86 Ctenotus mimetes Ctenotus astarte 88 Ctenotus septenarius 73 Ctenotus regius 63 Ctenotus olympicus 97 Ctenotus maryani Ctenotus atlas 66 Ctenotus grandis 90 Ctenotus angusticeps 51 Ctenotus hanloni 79 Ctenotus piankai 92 85 Ctenotus essingtonii Ctenotus hebetior 78 Ctenotus hilli Ctenotus gagudju 91 Ctenotus pulchellus 65 95 Lerista stylis Lerista karlschmidti Lerista carpentariae 81 100 Lerista ameles Lerista cinerea 99 Lerista wilkinsi 97 98 Lerista kalumburu Lerista apoda 91 Lerista griffini 100 Lerista ips 88 Lerista bipes 99 Lerista labialis Lerista greeri 93 Lerista robusta 98 100 Lerista vermicularis 90 Lerista simillima 99 Lerista walkeri 96 Lerista borealis Lerista frosti 97 Lerista fragilis 89 Lerista chordae Lerista xanthura 99 100 Lerista aericeps 90 Lerista taeniata 100 100 Lerista orientalis 100 Lerista ingrami Lerista zonulata 100 87 Lerista neander Lerista puncticauda 100 Lerista desertorum 79 Lerista eupoda 99 Lerista gerrardii Lerista axillaris 100 Lerista macropisthopus 93 Lerista microtis 100 Lerista arenicola Lerista edwardsae Lerista baynesi 100 Lerista picturata Lerista flammicauda 85 Lerista zietzi 100 Lerista speciosa 61 Lerista elongata 100 Lerista tridactyla 100 Lerista terdigitata 99 82 90 Lerista dorsalis Lerista punctatovittata Lerista emmotti 100 100 Lerista elegans 90 Lerista distinguenda Lerista christinae 87 Lerista lineata Lerista planiventralis 92 93 Lerista stictopleura 90 Lerista allochira Lerista haroldi 89 Lerista muelleri 96 Lerista viduata 93 Lerista bougainvillii 100 Lerista praepedita 100 Lerista humphriesi 93 Lerista petersoni 56 Lerista gascoynensis 100 Lerista nichollsi 89 81 Lerista kendricki 77 Lerista yuna 98 Lerista lineopunctulata Lerista varia 100 100 Lerista connivens 84 Lerista uniduo Lerista onsloviana 100 96 Lerista kennedyensis 100 Lygosominae 100 cont. G Figure 8 Species-level squamate phylogeny continued (G). Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 13 of 53 Tribolonotus novaeguineae Tribolonotus gracilis Tribolonotus blanchardi Tribolonotus schmidti 86 Tribolonotus brongersmai 97 Tribolonotus ponceleti 93 96 Tribolonotus pseudoponceleti Corucia zebrata Egernia saxatilis 86 Bellatorias major Egernia depressa 77 Egernia kingii Bellatorias frerei 90 Egernia richardi 100 74 Egernia napoleonis Lissolepis luctuosa 73 Egernia stokesii Egernia hosmeri 66 Cyclodomorphus michaeli 96 Cyclodomorphus casuarinae 97 Cyclodomorphus branchialis 81 Tiliqua adelaidensis Tiliqua rugosa 95 Tiliqua occipitalis 84 Tiliqua nigrolutea 71 Tiliqua gigas Tiliqua scincoides 100 91 88 Liopholis striata Liopholis inornata Liopholis multiscutata 98 Liopholis kintorei 90 Liopholis pulchra 85 99 73 Liopholis modesta Liopholis margaretae Liopholis whitii 56 Liopholis guthega 52 Liopholis montana 90 94 Ristella rurkii Lankascincus fallax Eutropis longicaudata Eutropis macularia 96 95 Eutropis rudis Eutropis macrophthalma 88 Eutropis multifasciata 100 Eutropis cumingi 90 Eutropis multicarinata 73 Eutropis clivicola 97 Eutropis bibronii Eutropis beddomii 100 96 Eutropis nagarjuni Eutropis trivittata 80 97 97 Dasia vittata Dasia grisea Dasia olivacea 93 Trachylepis aurata Trachylepis vittata 99 Trachylepis brevicollis Trachylepis socotrana Trachylepis maculilabris 83 98 91 100 Trachylepis wrightii Trachylepis sechellensis 99 Trachylepis affinis Trachylepis perrotetii 92 100 Trachylepis quinquetaeniata Trachylepis margaritifera 99 Trachylepis atlantica 84 54 Trachylepis varia Trachylepis capensis Trachylepis occidentalis 100 78 Trachylepis spilogaster 89 Trachylepis striata 100 Trachylepis hoeschi 99 100 90 Trachylepis variegata Trachylepis sulcata 95 Trachylepis homalocephala Trachylepis acutilabris Trachylepis gravenhorstii Trachylepis elegans 74 100 Trachylepis madagascariensis 95 98 Trachylepis boettgeri Trachylepis vato 100 Trachylepis aureopunctata 97 Trachylepis dumasi 95 Eumecia anchietae 90 91 Chioninia vaillantii 98 Chioninia delalandii Chioninia coctei Chioninia spinalis 80 Chioninia fogoensis Chioninia stangeri 87 100 Mabuya carvalhoi Mabuya croizati Mabuya nigropalmata Mabuya sloanii 100 78 Mabuya altamazonica Mabuya nigropunctata 98 Mabuya cochabambae 97 Mabuya dorsivittata 100 89 Mabuya meridensis Mabuya mabouya 96 Mabuya unimarginata 95 Mabuya falconensis 81 Mabuya bistriata Mabuya frenata 70 100 Mabuya agmosticha Mabuya macrorhyncha Mabuya guaporicola 77 Mabuya agilis 80 Mabuya caissara 100 99 Mabuya heathi 100 93 Lygosominae cont. 83 H Figure 9 Species-level squamate phylogeny continued (H). 100 Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 14 of 53 Ablepharus budaki Ablepharus chernovi Ablepharus kitaibelii 100 Sphenomorphus stellatus Emoia concolor Emoia tongana 96 63 98 60 95 93 92 76 Lygosominae 90 cont. 70 100 75 Lamprolepis smaragdina Lygosoma quadrupes Lygosoma koratense Lygosoma albopunctata Lepidothyris fernandi Lygosoma lineolatum Mochlus afer 100 Lygosoma sundevalli Lygosoma punctata Mochlus brevicaudis Lygosoma bowringii Eugongylus rufescens Eugongylus albofasciolatus Emoia loyaltiensis Leiolopis ma telfairii Leiolopisma mauriti ana 100 Panaspis breviceps Panaspis togoensis Afroablepharus wahlbergi Afroablepharus annobonensis Afroablepharus africanus 90 Lacertaspis reichenowi Lacertaspis rohdei 85 Lacertaspis chriswildi 93 91 Lacertaspis gemmiventris 96 Lacertaspis lepesmei Leptosiaphos hackarsi 100 Leptosiaphos graueri 95 Leptosiaphos amieti 81 Leptosiaphos kilimensis 95 Leptosiaphos vigintiserierum 99 Pseudemoia pagenstecheri 80 Bassiana duperreyi 99 Pseudemoia entrecasteauxii Oligosoma lichenigera Oligosoma suteri Oligosoma pikitanga 99 95 100 Oligosoma taumakae Oligosoma acrinasum Oligosoma infrapunctatum 98 100 Oligosoma waimatense 91 86 Oligosoma otagense 100 Oligosoma chloronoton 98 Oligosoma lineoocellatum 61 Oligosoma longipes 99 Oligosoma nigriplantare 99 Oligosoma grande 98 Oligosoma stenotis Oligosoma maccanni 90 85 100 100 Oligosoma inconspicuum 98 Oligosoma notosaurus Oligosoma zelandicum 100 Oligosoma homalonotum Oligosoma striatum 100 Oligosoma smithi 100 Oligosoma microlepis 94 93 Oligosoma aeneum Oligosoma levidensum 99 99 Oligosoma hardyi 57 Oligosoma fallai Oligosoma alani Oligosoma moco 98 63 Oligosoma macgregori 93 Oligosoma ornatum Oligosoma townsi 89 Oligosoma oliveri 9796 Oligosoma whitakeri Nannoscincus garrulus 98 Nannoscincus slevini 98 Nannoscincus gracilis 89 Nannoscincus mariei Nannoscincus greeri 82 94 Nannoscincus hanchisteus 93 Nannoscincus humectus Marmorosphax montana Marmorosphax tricolor 90 100 100 Celatiscincus similis 96 Celatiscincus euryotis Lioscincus vivae 96 Lioscincus steindachneri 96 Kanakysaurus viviparus Lioscincus nigrofasciolatum 84 80 Lacertoides pardalis 96 80 Phoboscincus garnieri Sigaloseps ruficauda Sigaloseps deplanchei 100 Lioscincus novaecaledoniae 85 Lioscincus maruia 85 Tropidoscincus aubrianus 98 92 Lioscincus tillieri Tropidoscincus boreus 100 100 Tropidoscincus variabilis Graciliscincus shonae 87 Simiscincus aurantiacus Caledoniscincus orestes 97 100 Caledoniscincus renevieri Caledoniscincus auratus 95 95 Caledoniscincus festivus Caledoniscincus austrocaledonicus 83 Caledoniscincus haplorhinus 97 Caledoniscincus atropunctatus 53 Caledoniscincus chazeaui 87 98 Caledoniscincus aquilonius 95 Caledoniscincus terma Cryptoblepharus nigropunctatus 100 Cryptoblepharus boutonii Cryptoblepharus novocaledonicus 79 93 93 Menetia greyii Menetia alanae Emoia schmidti 100 Emoia cyanogaster 91 Emoia caeruleocauda Emoia atrocostata 98 100 100 Emoia jakati Emoia physicae Emoia impar 77 Emoia cyanura 98 71 98 Emoia pseudocyanura 52 Emoia isolata Bassiana trilineata 73 Morethia ruficauda Morethia butleri Morethia adelaidensis Bartleia jigurru Saproscincus basiliscus 96 Saproscincus lewisi 96 72 Saproscincus czechurai 79 Saproscincus tetradactylus 98 Saproscincus hannahae 100 Saproscincus oriarus 76 Saproscincus mustelinus Saproscincus challengeri 71 Saproscincus rosei 100 100 Saproscincus spectabilis 97 Lampropholis guichenoti 92 Lampropholis delicata 100 Lampropholis coggeri Lampropholis robertsi Proablepharus reginae Niveoscincus greeni 72 Niveoscincus ocellatus 76 Niveoscincus pretiosus Niveoscincus metallicus 100 Cautula zia 87 Liburnascincus coensis 96 Liburnascincus scirtetis Liburnascincus mundivensis 91 88 Menetia timlowi 100 Carlia triacantha 98 Carlia johnstonei Carlia jarnoldae Carlia bicarinata 90 Carlia gracilis 79 Lygisaurus sesbrauna 75 Lygisaurus parrhasius 88 Lygisaurus macfarlani Lygisaurus novaeguineae 98 99 Lygisaurus aeratus Lygisaurus laevis 85 100 100Lygisaurus foliorum 78 Lygisaurus abscondita 68 100 Lygisaurus tanneri 89 Lygisaurus malleolus 91 Carlia schmeltzii Carlia storri Carlia fusca 98 Carlia longipes 100 Carlia mysi 73 93 Carlia munda 80 Carlia pectoralis Carlia rufilatus 85 100 Carlia rhomboidalis Carlia rubrigularis 92 Carlia tetradactyla Carlia amax Carlia rostralis 76 Carlia dogare 53 Carlia vivax 62 100 84 100 I Figure 10 Species-level squamate phylogeny continued (I). 99 99 85 Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 15 of 53 Callopistes flavipunctatus Callopistes maculatus Tupinambis rufescens Tupinambis merianae 100 Tupinambis duseni Tupinambis quadrilineatus 97 Tupinambis longilineus 98 Tupinambis teguixin 87 Crocodilurus amazonicus 54 66 Dracaena guianensis 91 Teius teyou 99 Ameiva ameiva Ameiva bifrontata 100 Cnemidophorus ocellifer 82 Kentropyx calcarata Kentropyx striata 71 Kentropyx altamazonica 100 Kentropyx pelviceps Kentropyx paulensis 91 56 Kentropyx vanzoi 96 Kentropyx viridistriga Ameiva undulata 100 Ameiva quadrilineata 97 Ameiva festiva 93 Cnemidophorus vanzoi Cnemidophorus gramivagus 99 Cnemidophorus lemniscatus Cnemidophorus arenivagus 94 Aspidoscelis inornata Aspidoscelis sexlineata 100 Aspidoscelis burti 99 Aspidoscelis communis 99 93 Aspidoscelis costata 98 99 Aspidoscelis gularis 81 83 Aspidoscelis laredoensis Aspidoscelis velox Aspidoscelis deppei 98 Aspidoscelis guttata Aspidoscelis lineattissima 100 Aspidoscelis marmorata 84 Aspidoscelis tigris 92 Aspidoscelis hyperythra Aspidoscelis ceralbensis 98 Ameiva auberi Ameiva dorsalis 100 Ameiva polops 86 Ameiva exsul 99 Ameiva wetmorei 97 Ameiva leberi Ameiva chrysolaema 59 100 Ameiva taeniura 96 Ameiva lineolata 95 100 Ameiva maynardi 100 Ameiva plei Ameiva corax Ameiva pluvianotata 98 Ameiva griswoldi 100 Ameiva erythrocephala 93 Ameiva fuscata 94 Dicrodon guttulatum 55 Cnemidophorus longicaudus 85 Cnemidophorus lacertoides 97 Ptychoglossus brevifrontalis Alopoglossus atriventris 100 99 Alopoglossus copii 100 Alopoglossus angulatus Ecpleopus gaudichaudii Leposoma nanodactylus Leposoma baturitensis Leposoma puk 100 100 Leposoma scincoides 98 Leposoma annectans 97 Colobosauroides cearensis 97 Anotosaura collaris 100 Arthrosaura reticulata 99 Arthrosaura kockii 86 Leposoma percarinatum 65 96 Leposoma osvaldoi 100 Leposoma parietale 98 Leposoma southi 95 Leposoma guianense Riama unicolor 100 Riama colomaromani Riama simoterus 91 Neusticurus rudis Neusticurus bicarinatus 94 99 Placosoma cordylinum 98 Placosoma glabellum 100 Pholidobolus montium Pholidobolus macbrydei 100 80 Potamites ecpleopus Potamites juruazensis 92 100 Cercosaura quadrilineata 98 100 Cercosaura oshaughnessyi Cercosaura argulus 97 Cercosaura ocellata 99 100 Cercosaura schreibersii Cercosaura eigenmanni 82 55 Proctoporus sucullucu Proctoporus subsolanus Proctoporus pachyurus 98 100 Proctoporus guentheri Proctoporus unsaacae Proctoporus bolivianus 94 99 Petracola ventrimaculatus Bachia flavescens Bachia bresslaui 100 Bachia dorbignyi 77 100 Bachia huallagana Bachia scolecoides 100 Bachia trisanale 88 Bachia panoplia 97 Bachia peruana 95 100 Bachia bicolor 84 78 Bachia barbouri 74 Bachia intermedia 98 Bachia heteropa Rhachisaurus brachylepis Heterodactylus imbricatus 100 Colobodactylus dalcyanus 93 Colobodactylus taunayi 99 Iphisa elegans 100 100 Colobosaura modesta Stenolepis ridleyi 91 96 Acratosaura mentalis Tretioscincus agilis Tretioscincus oriximinensis 98 72 Micrablepharus atticolus 100 Micrablepharus maximiliani Vanzosaura rubricauda 98 Procellosaurinus erythrocercus 61 100 Procellosaurinus tetradactylus 100 93 Nothobachia ablephara Calyptommatus sinebrachiatus Calyptommatus confusionibus 88 Calyptommatus leiolepis 93 50 86 Calyptommatus nicterus Psilophthalmus paeminosus Gymnophthalmus pleei Gymnophthalmus leucomystax 100 Gymnophthalmus vanzoi Gymnophthalmus speciosus 100 Gymnophthalmus underwoodi 87 100 Gymnophthalmus cryptus Tupinambinae 97 100 Teiidae Teiinae 100 Alopoglossinae Ecpleopinae Gymnophthalmidae Cercosaurinae Bachiinae Rhachisaurinae Gymnophthalminae J Figure 11 Species-level squamate phylogeny continued (J). Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 16 of 53 Rhineuridae Rhineura floridana Bipes tridactylus Bipedidae Bipes biporus 100 99 73 Bipes canaliculatus Blanus strauchi 100 100 Blanus cinereus Blanus mettetali 100 97 Blanidae Blanus tingitanus 84 Cadea blanoides Cadeidae Diplometopon zarudnyi 100 Trogonophiidae Trogonophis wiegmanni Cynisca leucura 100 100 Chirindia swynnertoni Geocalamus acutus Monopeltis capensis 91 Amphisbaenidae Amphisbaena brasiliana 89 Amphisbaena fuliginosa 55 Amphisbaena cunhai 95 86 Amphisbaena mertensii Amphisbaena hyporissor 96 67 81 Amphisbaena innocens Amphisbaena leali Amphisbaena ignatiana 91 Amphisbaena saxosa 100 Amphisbaena kraoh 100 100 Amphisbaena roberti Amphisbaena vermicularis 98 Amphisbaena alba Amphisbaena camura 95 100 Amphisbaena bolivica Amphisbaena anomala 89 Amphisbaena polystegum 100 Amphisbaena microcephalum 100 Amphisbaena infraorbitale 90 Amphisbaena hastata 100 Amphisbaena cuiabana 78 Amphisbaena kingii 100 Amphisbaena munoai 99 Amphisbaena darwini 93 Amphisbaena angustifrons 95 Amphisbaena leeseri Amphisbaena silvestrii 100 Amphisbaena anaemariae 100 Amphisbaena barbouri Amphisbaena cubana Amphisbaena carlgansi 90 Amphisbaena schmidti 92 Amphisbaena manni 97 87 K Figure 12 Species-level squamate phylogeny continued (K). 100 100 Amphisbaena fenestrata Amphisbaena caeca Amphisbaena bakeri Amphisbaena xera Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 17 of 53 Gallotiinae 99 100 95 99 95 68 Psammodromus hispanicus Psammodromus algirus Psammodromus blanci Gallotia stehlini Gallotia atlantica Gallotia galloti Gallotia caesaris Gallotia intermedia Gallotia simonyi 100 97 Gallotia bravoana Atlantolacerta andreanskyi Poromera fordii Nucras lalandii Latastia longicaudata Philochortus spinalis Pseuderemias smithii Heliobolus lugubris 90 Heliobolus spekii 84 99 Australolacerta australis Tropidosaura gularis 54 Ichnotropis capensis Meroles reticulatus Meroles knoxii 92 Meroles suborbitalis 100 Ichnotropis squamulosa 80 Meroles anchietae 76 Meroles ctenodactylus 97 100 97 Meroles micropholidotus Meroles cuneirostris Pedioplanis lineoocellata Nucras tessellata 100 Pedioplanis laticeps 100 Pedioplanis burchelli Pedioplanis breviceps Pedioplanis namaquensis 96 Pedioplanis husabensis 69 100 Pedioplanis undata Pedioplanis rubens 76 96 Pedioplanis inornata 96 Pedioplanis gaerdesi 56 100 Holaspis laevis Holaspis guentheri 100 100 Gastropholis vittata Gastropholis prasina Adolfus africanus 72 89 Adolfus alleni 96 99 Adolfus jacksoni Eremias brenchleyi Eremias argus 97 Eremias vermiculata Eremias velox 76 99 Eremias montanus 100 Eremias persica Eremias nigrolateralis 95 Eremias arguta Eremias przewalskii 93 Eremias multiocellata 100 93 Eremias pleskei 56 Eremias grammica 86 Congolacerta vauereselli Omanosaura cyanura Omanosaura jayakari 98 97 Mesalina simoni 100 Mesalina olivieri Mesalina bahaeldini Mesalina guttulata 100 91 Mesalina balfouri 89 Mesalina adramitana 93 Mesalina brevirostris 63 Mesalina rubropunctata Ophisops occidentalis Ophisops elegans 100 Acanthodactylus orientalis Acanthodactylus tristrami 100 Acanthodactylus blanci 95 Acanthodactylus erythrurus 99 73 Acanthodactylus busacki 94 Acanthodactylus beershebensis 100 Acanthodactylus pardalis 76 Acanthodactylus maculatus 86 100 Acanthodactylus aureus Acanthodactylus scutellatus 95 Acanthodactylus longipes 93 80 Acanthodactylus schmidti 99 Acanthodactylus cantoris Acanthodactylus masirae 96 Acanthodactylus gongrorhynchatus 100 Acanthodactylus opheodurus 85 Acanthodactylus boskianus 75 Acanthodactylus schreiberi 99 100 Phoenicolacerta kulzeri 98 Phoenicolacerta laevis Phoenicolacerta cyanisparsa Zootoca vivipara 95 Takydromus kuehnei 100 Takydromus sexlineatus Takydromus tachydromoides 100 Takydromus smaragdinus Takydromus sauteri 95 85 Takydromus intermedius 100 Takydromus dorsalis 100 Takydromus sylvaticus Takydromus amurensis 79 100 99 Takydromus hsuehshanensis Takydromus formosanus 100 Takydromus wolteri 97 100 Takydromus toyamai Takydromus septentrionalis 99 Takydromus stejnegeri 75 Timon princeps 94 Timon pater Timon lepidus 99 98 69 Timon tangitanus Lacerta viridis 58 100 Lacerta bilineata 100 Lacerta strigata 80 Lacerta schreiberi Lacerta agilis 92 Lacerta media 98 Lacerta trilineata 99 Lacerta pamphylica 98 100 Teira dugesii Scelarcis perspicillata Podarcis melisellensis 85 Podarcis tauricus Podarcis milensis 62 74 Podarcis gaigeae 55 Podarcis filfolensis 99 85 Podarcis tiliguerta 100 Podarcis muralis Podarcis siculus 92 95 Podarcis pityusensis Podarcis lilfordi 94 78 Podarcis raffoneae Podarcis erhardii Podarcis peloponnesiacus 88 79 Podarcis liolepis Podarcis vaucheri 93 Podarcis hispanicus 97 100 92 Podarcis bocagei Podarcis carbonelli 97 Dalmatolacerta oxycephala Hellenolacerta graeca 92 Archaeolacerta bedriagae Apathya cappadocica 91 Iberolacerta galani 86 86 Iberolacerta cyreni Iberolacerta monticola 100 Iberolacerta horvathi 100 Iberolacerta aurelioi Iberolacerta bonnali 93 Iberolacerta aranica 100 Parvilacerta fraasii 99 Parvilacerta parva 64 Anatololacerta anatolica 100 Anatololacerta oertzeni 89 Anatololacerta danfordi 96 Algyroides moreoticus Algyroides nigropunctatus 100 73 100 Dinarolacerta mosorensis Dinarolacerta montenegrina 94 Algyroides marchi 98 Algyroides fitzingeri 53 Iranolacerta brandtii 99 Iranolacerta zagrosica Darevskia parvula 97 Darevskia rudis Darevskia portschinskii 100 100 94 Darevskia valentini Darevskia praticola Darevskia chlorogaster 100 Darevskia alpina 96 Darevskia lindholmi Darevskia brauneri 100 Darevskia saxicola 87 rostombekovi 100 Darevskia 97 Darevskia raddei Darevskia uzzelli Darevskia sapphirina 100 Darevskia bendimahiensis 93 94 Darevskia armeniaca Darevskia clarkorum Darevskia mixta 98 Darevskia daghestanica 70 Darevskia caucasica 99 Darevskia derjugini 90 73 96 Lacertidae 100 Lacertinae L Figure 13 Species-level squamate phylogeny continued (L). 99 88 100 Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 18 of 53 Xenosauridae 100 Xenosaurus platyceps Xenosaurus grandis Helodermatidae 100 Heloderma suspectum 100 Heloderma horridum Anniellidae Anniella pulchra Anniella geronimensis Celestus enneagrammus Diploglossus bilobatus 98 Diploglossus pleii Diploglossinae Ophiodes striatus 100 100 Celestus agasepsoides 100 93 Celestus haetianus Ophisaurus ventralis Ophisaurus koellikeri 100 83 Pseudopus apodus Anguidae 90 Anguis fragilis Anguinae 99 87 Ophisaurus attenuatus Dopasia gracilis Dopasia harti 100 Elgaria coerulea 100 100 Elgaria kingii Elgaria paucicarinata 99 85 Elgaria panamintina 84 Elgaria multicarinata 100 Gerrhonotus parvus Gerrhonotinae 88 Coloptychon rhombifer Gerrhonotus liocephalus 92 100 Gerrhonotus infernalis Abronia mixteca 97 Barisia levicollis 100 Barisia imbricata Barisia herrerae 89 95 94 Barisia rudicollis Mesaspis moreletii 79 Mesaspis gadovii 72 Abronia chiszari 66 Abronia oaxacae Abronia graminea 99 Abronia frosti Abronia ornelasi 96 84 Abronia lythrochila 89 Abronia fimbriata Abronia matudai 96 Abronia anzuetoi 97 95 Abronia campbelli Abronia aurita Shinisauridae Shinisaurus crocodilurus Lanthanotidae Lanthanotus borneensis Varanus griseus Varanus niloticus 94 Varanus exanthematicus 95 Varanus albigularis 97 99 Varanus yemenensis 100 Varanus olivaceus 98 Varanus keithhornei 100 Varanus beccarii 95 95 Varanus boehmei Varanidae Varanus macraei 100 75 Varanus prasinus 86 Varanus rainerguentheri 86 78Varanus indicus Varanus melinus 88 Varanus cerambonensis 100 Varanus caerulivirens Varanus jobiensis Varanus yuwonoi 76 Varanus doreanus 100 79 74 Varanus finschi 86 Varanus marmoratus Varanus salvator 100 69 Varanus rudicollis Varanus dumerilii Varanus flavescens 85 72 Varanus bengalensis Varanus mertensi 100 Varanus spenceri 84 Varanus giganteus Varanus rosenbergi 92 Varanus panoptes 96 94 Varanus gouldii Varanus salvadorii 100 100 Varanus varius 99 Varanus komodoensis Varanus glebopalma 99 Varanus pilbarensis 100 Varanus tristis 87 Varanus glauerti Varanus scalaris 96 Varanus timorensis 76 Varanus mitchelli 86 100 100 Varanus semiremex Varanus brevicauda 100 Varanus eremius Varanus caudolineatus 88 100 Varanus gilleni 100 Varanus bushi Varanus kingorum 97 99 Varanus primordius Varanus storri 99 Varanus acanthurus 100 Varanus baritji 99 100 95 M Figure 14 Species-level squamate phylogeny continued (M). Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 19 of 53 79 Brookesia lolontany Brookesia nasus Brookesia dentata 100 Brookesia exarmata Brookesia minima 63 Brookesia tuberculata 100 Brookesia karchei 83 Brookesia peyrierasi 100 Brookesia perarmata 100 Brookesia decaryi 98 Brookesia brygooi 100 Brookesia bonsi Brookesia therezieni 100 99 Brookesia superciliaris 93 Brookesia valerieae Brookesia griveaudi 100 Brookesia stumpffi 100 Brookesia ambreensis Brookesia antakarana Brookesia ebenaui Brookesia vadoni 100 Brookesia thieli Brookesia betschi 51 Brookesia lineata Furcifer balteatus 99 Furcifer bifidus Furcifer minor 62 99 Furcifer willsii Furcifer petteri 86 Furcifer campani 93 96 Furcifer cephalolepis 91 Furcifer polleni 100 Furcifer pardalis 94 Furcifer angeli Furcifer oustaleti 99 93 Furcifer verrucosus Furcifer belalandaensis 98 Furcifer lateralis 98 94 Furcifer labordi 100 Furcifer antimena 100 Kinyongia oxyrhina Kinyongia tenue Kinyongia adolfifriderici 95 100 Kinyongia excubitor Kinyongia xenorhina 67 Kinyongia carpenteri 98 82 Kinyongia uthmoelleri Kinyongia tavetana 100 100 Kinyongia boehmei 92 Kinyongia matschiei 55 100 Kinyongia multituberculata 100 Kinyongia vosseleri 59 100 Kinyongia fischeri 96 Bradypodion pumilum Bradypodion damaranum Bradypodion caffer 100 Bradypodion melanocephalum 100 Bradypodion thamnobates 94 98 Bradypodion transvaalense Bradypodion dracomontanum 72 87 Bradypodion nemorale Bradypodion setaroi Bradypodion occidentale Bradypodion atromontanum 85 Bradypodion gutturale 98 Bradypodion taeniabronchum 74 95 Bradypodion karrooicum Bradypodion ventrale 95 100 Calumma furcifer 99 Calumma gastrotaenia Rieppeleon kerstenii Rieppeleon brachyurus 100 Rieppeleon brevicaudatus 58 Calumma cucullatum Calumma crypticum 88 100 82 Calumma brevicorne 98 Calumma tsaratananense Calumma hilleniusi 100 75 Calumma guibei Calumma malthe 91 Calumma gallus 93 78 Calumma fallax 85 Calumma boettgeri 97 94 Calumma nasutum Nadzikambia mlanjensis Rhampholeon spectrum 73 Rhampholeon temporalis 88 Rhampholeon spinosus 98 98 Rhampholeon viridis 99 Rhampholeon marshalli Rhampholeon moyeri 86 Rhampholeon uluguruensis Rhampholeon acuminatus 100 81 Rhampholeon boulengeri 73 Rhampholeon beraduccii Rhampholeon nchisiensis 91 Rhampholeon platyceps 90 100 Rhampholeon chapmanorum 100 Calumma capuroni Calumma oshaughnessyi Calumma parsonii 100 Calumma globifer 95 61 Chamaeleo namaquensis Chamaeleo laevigatus Chamaeleo necasi 99 100 Chamaeleo gracilis 90 Chamaeleo quilensis 100 Chamaeleo dilepis 99 Chamaeleo roperi Chamaeleo senegalensis Chamaeleo monachus 95 Chamaeleo africanus Chamaeleo calcaricarens Chamaeleo chamaeleon 85 100 Chamaeleo zeylanicus Chamaeleo calyptratus 98 100 Chamaeleo arabicus 100 Trioceros affinis Trioceros harennae 100 Trioceros balebicornutus 66 Trioceros feae Trioceros montium 100 85 Trioceros cristatus 100 Trioceros wiedersheimi Trioceros quadricornis 96 100 50 Trioceros pfefferi 97 Trioceros oweni Trioceros johnstoni 93 Trioceros melleri Trioceros deremensis 98 92 Trioceros werneri Trioceros tempeli 92 Trioceros goetzei 97 91 Trioceros fuelleborni Trioceros bitaeniatus 70 Trioceros jacksonii 98 90 Trioceros narraioca Trioceros schubotzi Trioceros hoehnelii 85 Trioceros ellioti 87 Trioceros rudis 97 66 Trioceros sternfeldi 100 Chamaeleonidae 100 Chamaeleoninae N Figure 15 Species-level squamate phylogeny continued (N). Brookesiinae Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 20 of 53 Uromastyx hardwickii Uromastyx loricata Uromastyx asmussi 95 Uromastyx princeps 100 Uromastyx macfadyeni Uromastyx geyri 86 100 Uromastyx acanthinura 74 Uromastyx dispar 94 Uromastyx thomasi Uromastyx aegyptia 100 Uromastyx leptieni 91 Uromastyx ornata 99 70 Uromastyx ocellata Uromastyx benti 100 100 Uromastyx yemenensis 100 Leiolepis belliana Leiolepis reevesii 100 100 Leiolepis guttata Leiolepis guentherpetersi Hydrosaurus amboinensis Physignathus cocincinus Hypsilurus spinipes 92 Hypsilurus boydii 97 Hypsilurus dilophus 85 Moloch horridus 98 Chelosania brunnea 100 Hypsilurus modestus 100 Hypsilurus papuensis Hypsilurus nigrigularis 100 51 Hypsilurus bruijnii Intellagama lesueurii Ctenophorus maculosus 100 75 Ctenophorus adelaidensis Ctenophorus clayi 100 Ctenophorus gibba 96 Ctenophorus salinarum Ctenophorus cristatus 100 Ctenophorus nuchalis 98 Ctenophorus reticulatus 71 Ctenophorus rufescens 99 Ctenophorus tjantjalka Ctenophorus vadnappa 99 Ctenophorus decresii Ctenophorus fionni 79 90 Ctenophorus caudicinctus 100 Ctenophorus ornatus Ctenophorus isolepis 100 53 92 Ctenophorus scutulatus 100 Ctenophorus mckenziei 76 Ctenophorus pictus Ctenophorus maculatus 90 Ctenophorus fordi 100 94 Ctenophorus femoralis Lophognathus temporalis 71 Lophognathus longirostris Chlamydosaurus kingii 100 Lophognathus gilberti 94 Amphibolurus muricatus Amphibolurus norrisi 97 100 Tympanocryptis uniformis 100 Tympanocryptis intima 99 Tympanocryptis tetraporophora Tympanocryptis cephalus Tympanocryptis pinguicolla 71 100 53 Tympanocryptis lineata Rankinia diemensis 63 Pogona barbata 100 Pogona nullarbor 99 Pogona henrylawsoni Pogona minima 99 99 Pogona minor 94 Pogona vitticeps Diporiphora superba Diporiphora linga 99 Diporiphora winneckei 81 Diporiphora reginae Diporiphora magna 76 Diporiphora bilineata 67 Diporiphora pindan 95 100 Diporiphora valens Diporiphora amphiboluroides Diporiphora australis Diporiphora nobbi 95 Diporiphora bennettii 56 Diporiphora albilabris 100 Diporiphora arnhemica 95 Diporiphora lalliae Agaminae Uromastycinae Leiolepidinae 100 Hydrosaurinae Amphibolurinae Agamidae (i) 96 (i) (ii) 100 100 Draconinae (ii) 100 O Figure 16 Species-level squamate phylogeny continued (O). Laudakia stellio Laudakia sacra Laudakia tuberculata Laudakia nupta Laudakia lehmanni 85 Laudakia himalayana Laudakia stoliczkana 84 99 Laudakia microlepis 84 Laudakia caucasia 88 100 Laudakia erythrogaster Phrynocephalus scutellatus Phrynocephalus interscapularis Phrynocephalus forsythii 100 100 Phrynocephalus theobaldi Phrynocephalus putjatai 64 90 75 Phrynocephalus vlangalii 73 Phrynocephalus lidskii Phrynocephalus axillaris Phrynocephalus helioscopus Phrynocephalus mystaceus 91 Phrynocephalus raddei 100 89 100 Phrynocephalus versicolor Phrynocephalus przewalskii 94 melanurus Phrynocephalus 100 Phrynocephalus albolineatus 96 90 Phrynocephalus guttatus Pseudotrapelus sinaitus 100 Acanthocercus atricollis 66 Xenagama taylori 95 Bufoniceps laungwalaensis Trapelus sanguinolentus 100 Trapelus mutabilis 99 Trapelus agilis Trapelus ruderatus Trapelus pallidus 99 93 Trapelus flavimaculatus 89 100 Trapelus savignii 100 Agama spinosa Agama boueti 100 Agama impalearis 100 96 Agama castroviejoi Agama boulengeri 76 Agama insularis 100 Agama gracilimembris 84 Agama weidholzi 69 Agama anchietae Agama atra 100 100 91 Agama hispida Agama armata 50 Agama aculeata 100 Agama caudospinosa Agama rueppelli 100 Agama lionotus Agama kaimosae 91 Agama mwanzae 65 98 Agama sankaranica Agama doriae 99 Agama agama 100 Agama finchi 100 Agama planiceps 68 Agama paragama 68 Mantheyus phuwuanensis Japalura variegata 70 Japalura tricarinata 100 Ptyctolaemus gularis Ptyctolaemus collicristatus 100 Draco dussumieri Draco lineatus Draco maculatus 95 Draco fimbriatus 86 Draco cristatellus 99 97 53 Draco maximus Draco mindanensis Draco quinquefasciatus 92 100 melanopogon 65 Draco haematopogon 59 95 Draco Draco indochinensis 96 Draco blanfordii Draco taeniopterus 61 86 Draco obscurus 100 100 Draco spilonotus Draco caerulhians 100 97 Draco biaro Draco beccarii Draco bourouniensis 100 Draco rhytisma 99 95 Draco bimaculatus Draco volans 100 Draco timorensis 99 Draco boschmai 100 Draco reticulatus 100 Draco cyanopterus Draco quadrasi Draco guentheri 91 Draco cornutus Draco spilopterus 85 Draco palawanensis Draco ornatus 87 Phoxophrys nigrilabris Japalura polygonata Gonocephalus robinsonii 100 Aphaniotis fusca 97 98 Coryphophylax subcristatus Bronchocela cristatella Gonocephalus grandis 85 Gonocephalus chamaeleontinus 87 100 Gonocephalus kuhlii 86 Lyriocephalus scutatus 97 52 Cophotis dumbara 100 Cophotis ceylanica 100 Ceratophora aspera Ceratophora karu Ceratophora stoddartii 90 100 Ceratophora erdeleni Calotes mystaceus 72 81 Calotes chincollium 100 Calotes emma 55 Calotes liocephalus Calotes ceylonensis 100 90 99 Calotes nigrilabris Calotes liolepis 99 Calotes versicolor 100 Calotes irawadi 50 Calotes calotes Calotes htunwini 91 Salea horsfieldii Acanthosaura crucigera Acanthosaura armata 100 96 Acanthosaura capra Acanthosaura lepidogaster 69 Sitana ponticeriana 100 Otocryptis wiegmanni Japalura flaviceps 100 Japalura splendida Pseudocalotes kakhienensis 99 Pseudocalotes brevipes 100 Pseudocalotes flavigula 95 94 94 99 Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 21 of 53 P 94 Stenocercus scapularis Stenocercus apurimacus Stenocercus formosus Stenocercus ochoai 94 Stenocercus roseiventris 64 Stenocercus azureus Stenocercus doellojuradoi 100 100 69 Stenocercus limitaris Stenocercus caducus 88 Stenocercus ornatus Stenocercus percultus 100 78 Stenocercus puyango 100 Stenocercus iridescens Stenocercus angulifer 96 89 Stenocercus rhodomelas Stenocercus chota 84 82 Stenocercus festae 99 Stenocercus guentheri 96 100 Stenocercus angel Stenocercus humeralis Stenocercus marmoratus 71 Stenocercus crassicaudatus 100 100 Stenocercus torquatus Stenocercus varius 73 Stenocercus imitator 89 Stenocercus eunetopsis 94 Stenocercus empetrus Tropiduridae 100 Stenocercus boettgeri 88 100 Stenocercus cupreus 78 Stenocercus chrysopygus 79 Stenocercus ornatissimus Stenocercus orientalis 100 Stenocercus latebrosus 85 Stenocercus melanopygus 88 Stenocercus stigmosus Microlophus thoracicus 100 Microlophus theresiae Microlophus heterolepis 100 99 96 Microlophus tigris Microlophus peruvianus 100 Microlophus quadrivittatus 100 Microlophus atacamensis 100 Microlophus theresioides 98 Microlophus yanezi Microlophus koepckeorum Microlophus occipitalis 100 Microlophus bivittatus 100 100 Microlophus habelii Microlophus stolzmanni Microlophus delanonis 100 Microlophus grayii 100 Microlophus pacificus 100 64 Microlophus albemarlensis 95 Microlophus duncanensis Uranoscodon superciliosus 74 Uracentron flaviceps Tropidurus bogerti 98 Strobilurus torquatus Plica umbra 78 Plica lumaria 99 Plica plica 100 Tropidurus callathelys 100 Tropidurus spinulosus 100 100 Eurolophosaurus divaricatus 100 Eurolophosaurus amathites Eurolophosaurus nanuzae Tropidurus hygomi Tropidurus montanus 100 100 Tropidurus psammonastes Tropidurus itambere 73 98 Tropidurus cocorobensis 97 83 Tropidurus etheridgei Tropidurus mucujensis Tropidurus erythrocephalus Tropidurus insulanus Tropidurus oreadicus 100 Tropidurus hispidus 98 Iguanidae 89 Tropidurus torquatus Dipsosaurus dorsalis Brachylophus fasciatus 100 Brachylophus vitiensis 99 Iguana iguana 92 Iguana delicatissima Sauromalus ater 100 100 Sauromalus klauberi Sauromalus hispidus 61 Sauromalus varius Cyclura pinguis 100 94 Cyclura cornuta 100 Cyclura ricordi 97 Cyclura carinata 95 Cyclura collei Cyclura rileyi 57 Cyclura nubila 85 86 Cyclura cychlura 56 Amblyrhynchus cristatus 100 Conolophus subcristatus 72 Conolophus pallidus Ctenosaura similis 62 Ctenosaura hemilopha 100 96 Ctenosaura acanthura 99 Ctenosaura pectinata 99 98 Ctenosaura melanosterna Ctenosaura oedirhina Ctenosaura bakeri 100 74 Ctenosaura palearis Ctenosaura flavidorsalis 99 Ctenosaura quinquecarinata 72 Ctenosaura oaxacana 86 Q-R Figure 17 Species-level squamate phylogeny continued (P). Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 22 of 53 69 100 (i) 81 Q Figure 18 Species-level squamate phylogeny continued (Q). Opluridae 99 Enyaliinae Leiosaurinae 95 96 (ii) 63 Liolaemidae 54 Phrynosomatidae (i) Polychrus gutturosus Polychrus acutirostris Polychrus femoralis Polychrus marmoratus Hoplocercus spinosus 100 Morunasaurus annularis 100 Enyalioides laticeps Enyalioides heterolepis 88 Enyalioides oshaughnessyi Enyalioides palpebralis 96 Enyalioides microlepis 96 Enyalioides praestabilis 96 Chalarodon madagascariensis 90 Oplurus cyclurus Oplurus cuvieri 99 Oplurus quadrimaculatus 100 Oplurus saxicola 73 Oplurus grandidieri 96 Oplurus fierinensis 88 Enyalius bilineatus Enyalius leechii 97 Urostrophus gallardoi Anisolepis longicauda 99 Urostrophus vautieri 100 Pristidactylus scapulatus 98 Diplolaemus darwinii 100 Pristidactylus torquatus Leiosaurus bellii 78 Leiosaurus paronae 77 Leiosaurus catamarcensis 70 Ctenoblepharys adspersa Phymaturus indistinctus 100 Phymaturus somuncurensis 100 98 Phymaturus patagonicus 100 Phymaturus dorsimaculatus Phymaturus palluma punae 96 Phymaturus mallimaccii 89 Phymaturus Phymaturus antofagastensis 88 Liolaemus tenuis Liolaemus lemniscatus 95 99 Liolaemus monticola 100 Liolaemus nitidus Liolaemus nigroviridis 68 93 Liolaemus fuscus Liolaemus atacamensis 100 Liolaemus zapallarensis Liolaemus pseudolemniscatus 91 Liolaemus nigromaculatus 67 Liolaemus platei 66 97 Liolaemus paulinae 99 99 Liolaemus austromendocinus thermarum 100 Liolaemus Liolaemus dicktracyi 100 Liolaemus heliodermis 95 Liolaemus capillitas 98 83 Liolaemus umbrifer Liolaemus petrophilus 100 Liolaemus buergeri Liolaemus ceii 59 Liolaemus leopardinus 100 100 Liolaemus kriegi 66 Liolaemus elongatus 98 Liolaemus coeruleus Liolaemus bellii 98 Liolaemus gravenhorstii 97 Liolaemus schroederi 100 Liolaemus chiliensis 99 Liolaemus cyanogaster 98 Liolaemus pictus 99 Liolaemus hernani 86 Liolaemus bibronii Liolaemus pagaburoi 56 Liolaemus bitaeniatus 53 Liolaemus chaltin 100 100 100 Liolaemus puna 68 Liolaemus walkeri 97 yanalcu 91 Liolaemus Liolaemus ramirezae Liolaemus robertmertensi 74 Liolaemus gracilis 84 100 Liolaemus saxatilis Liolaemus hatcheri 94 Liolaemus lineomaculatus 70 Liolaemus silvanae 100 Liolaemus kolengh Liolaemus magellanicus 100 Liolaemus uptoni 99 Liolaemus somuncurae 100 100 Liolaemus baguali tari 100 95 Liolaemus Liolaemus escarchadosi Liolaemus kingii 100 gallardoi 83 Liolaemus Liolaemus sarmientoi 99 Liolaemus scolaroi zullyae 98 Liolaemus 78 Liolaemus tristis Liolaemus archeforus 100 Liolaemus stolzmanni Liolaemus orientalis 100 famatinae 98 Liolaemus Liolaemus vallecurensis 82 82 Liolaemus ruibali Liolaemus 78 99 Liolaemus audituvelatus 72 fabiani Liolaemus huacahuasicus Liolaemus dorbignyi 84 Liolaemus molinai 87 Liolaemus multicolor Liolaemus andinus 100 Liolaemus pseudoanomalus 100 Liolaemus occipitalis 97 99 Liolaemus lutzae Liolaemus salinicola 65 85 Liolaemus riojanus 100 Liolaemus multimaculatus 99 Liolaemus scapularis Liolaemus azarai 98 Liolaemus wiegmannii 100 Liolaemus rothi 100 Liolaemus boulengeri 99 Liolaemus inacayali Liolaemus telsen 85 Liolaemus cuyanus 99 Liolaemus donosobarrosi Liolaemus melanops 100 Liolaemus canqueli 98 93 Liolaemus morenoi Liolaemus chehuachekenk 64 95 Liolaemus fitzingerii 79 Liolaemus xanthoviridis Liolaemus hermannunezi Liolaemus uspallatensis 94 Liolaemus chacoensis 100 Liolaemus olongasta 78 Liolaemus grosseorum 95 Liolaemus darwinii 99 100 Liolaemus laurenti 100 Liolaemus koslowskyi 94 Liolaemus quilmes 100 Liolaemus espinozai 66 Liolaemus abaucan Liolaemus crepuscularis Liolaemus irregularis 99 100Liolaemus albiceps Liolaemus calchaqui 67 Liolaemus ornatus 86 Liolaemus lavillai 92 99 Polychrotidae Hoplocercidae Leiocephalidae Crotaphytidae 87 (ii) 93 R Leiosauridae Leiocephalus carinatus Leiocephalus raviceps Leiocephalus psammodromus Leiocephalus personatus Leiocephalus schreibersii 92 Leiocephalus barahonensis Gambelia wislizenii Gambelia sila 100 Gambelia copeii Crotaphytus antiquus 99 100 Crotaphytus reticulatus Crotaphytus vestigium 100 Crotaphytus insularis 100 82 Crotaphytus grismeri 83 Crotaphytus bicinctores Crotaphytus nebrius 93 100 Crotaphytus collaris Uma exsul Uma paraphygas 100 100 Uma scoparia Uma inornata 100 100 100 Uma notata Callisaurus draconoides Cophosaurus texanus 99 Holbrookia lacerata Holbrookia propinqua 100 99 Holbrookia maculata 100 Phrynosoma cornutum Phrynosoma solare 96 Phrynosoma mcallii 100 Phrynosoma platyrhinos 100 Phrynosoma coronatum Phrynosoma blainvillii 100 Phrynosoma cerroense 96 Phrynosoma wigginsi 95 Phrynosoma asio 88 Phrynosoma braconnieri 92 Phrynosoma taurus Phrynosoma modestum 100 Phrynosoma orbiculare 100 Phrynosoma ditmarsi 97 Phrynosoma douglassii 100 Phrynosoma hernandesi 99 Petrosaurus mearnsi 100 Petrosaurus repens 100 Petrosaurus thalassinus Uta squamata Uta palmeri 100 Uta stansburiana 76 100 Uta stejnegeri Urosaurus gadovi Urosaurus bicarinatus 100 100 Urosaurus lahtelai 100 99 Urosaurus nigricaudus Urosaurus graciosus 100 Urosaurus ornatus 99 Urosaurus clarionensis 100 100 Urosaurus auriculatus 96 Sceloporus parvus Sceloporus couchii 86 100 Sceloporus chrysostictus Sceloporus teapensis 100 Sceloporus variabilis Sceloporus smithi 91 Sceloporus cozumelae 97 Sceloporus grandaevus 90 Sceloporus angustus 100 100 Sceloporus utiformis Sceloporus carinatus Sceloporus squamosus 100 Sceloporus siniferus 100 75 Sceloporus merriami 95 Sceloporus pyrocephalus Sceloporus nelsoni 100 Sceloporus gadoviae 100 Sceloporus maculosus 82 Sceloporus jalapae 96 Sceloporus ochoterenae 100 Sceloporus vandenburgianus Sceloporus graciosus 100 99 Sceloporus arenicolus 89 Sceloporus magister 99 Sceloporus zosteromus Sceloporus lineatulus 100 99 Sceloporus licki 100 Sceloporus orcutti 100 99 Sceloporus hunsakeri Sceloporus melanorhinus Sceloporus grammicus 100 99 Sceloporus palaciosi Sceloporus heterolepis 97 Sceloporus aeneus 89 99 Sceloporus bicanthalis Sceloporus scalaris 100 99 Sceloporus slevini Sceloporus chaneyi 98 Sceloporus samcolemani 98 100 Sceloporus goldmani Sceloporus megalepidurus 96 Sceloporus insignis Sceloporus jarrovii 96 92 Sceloporus torquatus 89 97 Sceloporus bulleri 100 Sceloporus mucronatus Sceloporus macdougalli Sceloporus poinsettii 100 Sceloporus dugesii Sceloporus minor 98 Sceloporus ornatus 98 82 Sceloporus serrifer 98 100 Sceloporus cyanogenys Sceloporus clarkii Sceloporus olivaceus Sceloporus occidentalis Sceloporus virgatus 100 91 Sceloporus woodi 65 Sceloporus consobrinus 100 Sceloporus undulatus Sceloporus cautus 99 Sceloporus horridus 100 Sceloporus edwardtaylori 74 Sceloporus spinosus 100 Sceloporus taeniocnemis Sceloporus smaragdinus 100 98 Sceloporus malachiticus Sceloporus lundelli 100 Sceloporus cryptus 100 Sceloporus subpictus 61 Sceloporus formosus Sceloporus stejnegeri 100 Sceloporus adleri 97 94 100 Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 23 of 53 Laemanctus longipes Corytophanes percarinatus Corytophanes cristatus Basiliscus galeritus Basiliscus vittatus Basiliscus plumifrons 98 Basiliscus basiliscus 92 Anolis boettgeri 67 Anolis luciae Anolis bonairensis 64 Anolis griseus Anolis trinitatis 100 Anolis richardii 62 Anolis aeneus 96 Anolis roquet 100 Anolis extremus 100 100 Anolis fitchi 89 Anolis huilae Anolis peraccae 96 Anolis festae Anolis chloris 95 Anolis ventrimaculatus Anolis aequatorialis 99 96 Anolis gemmosus 90 Anolis euskalerriari Anolis nicefori 100 Anolis heterodermus 100 Anolis vanzolinii 99 Anolis inderenae 65 100 Anolis punctatus 83 Anolis transversalis 100 Anolis tigrinus Anolis jacare 99 Anolis anatoloros 100 71 98 Anolis calimae Anolis neblininus Anolis agassizi 100 Anolis microtus Anolis insignis 100 Anolis danieli 100 80 Anolis fraseri 98 Anolis chocorum Anolis princeps 87 100 Anolis frenatus 100 Anolis casildae Anolis maculigula 100 Anolis bartschi Anolis vermiculatus 75 Anolis occultus 79 Anolis monticola 82 Anolis darlingtoni Anolis bahorucoensis 99 56 100 Anolis dolichocephalus 100 Anolis hendersoni Anolis coelestinus 94 Anolis chlorocyanus Anolis singularis 100 99 Anolis aliniger 59 90 Anolis smallwoodi 100 Anolis noblei Anolis baracoae 59 Anolis luteogularis 89 Anolis equestris Anolis etheridgei 98 98 Anolis fowleri 100 Anolis insolitus 97 Anolis barbouri 86 Anolis olssoni 97 Anolis semilineatus 99 Anolis alumina Anolis argenteolus Anolis barbatus 95 100 Anolis porcus Anolis chamaeleonides 86 66 Anolis guamuhaya 86 Anolis cuvieri Anolis christophei Anolis eugenegrahami 93 90 Anolis ricordi 90 Anolis baleatus 100 95 Anolis barahonae Anolis marcanoi 100 Anolis strahmi 99 Anolis longitibialis Anolis haetianus 96 Anolis shrevei 99 Anolis armouri 95 Anolis cybotes 99 Anolis whitemani 60 Anolis lucius Anolis clivicola 97 Anolis rejectus Anolis cyanopleurus 100 100 Anolis cupeyalensis Anolis macilentus 99 Anolis alfaroi Anolis vanidicus 65 Anolis inexpectatus 76 100 Anolis alutaceus Anolis placidus 86 100 Anolis sheplani 85 Anolis alayoni Anolis paternus 100 100 Anolis angusticeps Anolis garridoi 80 100 Anolis guazuma 98 89 Anolis loysiana 97 Anolis pumilus Anolis centralis 100 Anolis argillaceus 95 Anolis oporinus 100 Anolis isolepis 100 Anolis carolinensis Anolis porcatus Anolis longiceps 99 Anolis brunneus Anolis maynardi 100 Anolis allisoni 74 97 Anolis smaragdinus 100 100 (i) 99 Dactyloidae (i) (ii) R Figure 19 Species-level squamate phylogeny continued (R). Corytophanidae Anolis wattsi Anolis pogus Anolis leachii Anolis bimaculatus 90 Anolis gingivinus Anolis oculatus 99 77 Anolis terraealtae Anolis ferreus 99 Anolis lividus 100 Anolis nubilus 95 100 Anolis sabanus 57 Anolis marmoratus Anolis distichus 100 Anolis websteri Anolis brevirostris 96 Anolis marron 94 100 Anolis caudalis Anolis acutus 95 100 Anolis stratulus Anolis evermanni Anolis poncensis 88 Anolis gundlachi 100 91 Anolis pulchellus 100 Anolis krugi 98 100 Anolis monensis Anolis cooki Anolis scriptus 100 Anolis ernestwilliamsi 96 Anolis desechensis 100 75 100 Anolis cristatellus Anolis imias 98 Anolis rubribarbaris Anolis allogus 100 98 Anolis ahli 90 Anolis guafe 100 Anolis confusus Anolis jubar 72 94 Anolis homolechis 100 Anolis mestrei Anolis ophiolepis 100 Anolis sagrei 99 Anolis quadriocellifer 89 99 Anolis bremeri Anolis lineatopus 100 Anolis reconditus 58 Anolis valencienni 100 Anolis opalinus 100 Anolis garmani 90 95 Anolis conspersus 100 Anolis grahami Anolis auratus 99 Anolis annectens 100 Anolis onca Anolis lineatus Anolis meridionalis 52 Anolis nitens 84 Anolis bombiceps 59 99 Anolis chrysolepis 99 Anolis loveridgei 100 Anolis purpurgularis 90 Anolis utilensis Anolis crassulus 96 Anolis sminthus 72 Anolis polyrhachis 94 Anolis uniformis Anolis bitectus Anolis biporcatus 95 Anolis woodi 100 Anolis aquaticus Anolis quercorum Anolis ortonii Anolis laeviventris 100 Anolis intermedius 93 92 Anolis isthmicus 100 Anolis sericeus Anolis pachypus 86 100 Anolis humilis 69 Anolis altae 100 86 Anolis kemptoni Anolis fuscoauratus 93 Anolis cupreus 98 Anolis polylepis Anolis capito 99 90 Anolis tropidonotus Anolis ocelloscapularis Anolis carpenteri 100 Anolis bicaorum 100 Anolis lemurinus 91 56 Anolis limifrons 100 Anolis zeus 94 Anolis oxylophus 86 Anolis lionotus 97 Anolis tropidogaster Anolis poecilopus 96 92 Anolis trachyderma 100 100 56 (ii) Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 24 of 53 Liotyphlops albirostris Typhlophis squamosus Tricheilostoma bicolor Siagonodon septemstriatus 93 97 Epictia albifrons 100 Epictia goudotii 100 Epictia columbi Trilepida macrolepis 97 100 Rena dulcis 100 Rena humilis 100 Tetracheilostoma carlae Tetracheilostoma breuili Mitophis asbolepis 100 100 100 Mitophis pyrites Mitophis leptipileptus 98 Myriopholis longicauda 100 Myriopholis algeriensis Myriopholis rouxestevae 56 100 Myriopholis boueti Myriopholis blanfordi 79 Myriopholis macrorhyncha 100 100 69 Myriopholis adleri Namibiana occidentalis Leptotyphlops nigroterminus 100 Leptotyphlops nigricans 99 100 Leptotyphlops sylvicolus Leptotyphlops conjunctus 100 Leptotyphlops distanti 51 Leptotyphlops scutifrons 100 91 Gerrhopilus hedraeus Gerrhopilus mirus Xenotyphlops grandidieri Typhlops brongersmianus 96 Typhlops reticulatus Typhlops biminiensis 100 Typhlops pusillus 95 Typhlops hectus 100 Typhlops syntherus 71 90 Typhlops eperopeus 87 Typhlops lumbricalis 84 Typhlops schwartzi 56 Typhlops titanops 100 92 83 Typhlops sulcatus 77 Typhlops rostellatus Typhlops capitulatus Typhlops jamaicensis 77 92 Typhlops sylleptor 92 99 Typhlops agoralionis Typhlops caymanensis 100 Typhlops arator Typhlops contorhinus 74 Typhlops anchaurus 100 Typhlops anousius Typhlops notorachius Typhlops monastus 100 Typhlops dominicanus Typhlops granti 86 Typhlops hypomethes 84 99 Typhlops platycephalus 95 Typhlops richardi 75 Typhlops catapontus Rhinotyphlops lalandei Letheobia feae 100 Letheobia newtoni 87 Letheobia obtusa Typhlops elegans 100 Afrotyphlops angolensis 100 Megatyphlops schlegelii 77 Afrotyphlops fornasinii 89 99 Afrotyphlops bibronii 87 Afrotyphlops lineolatus 87 Afrotyphlops congestus 99 72 Afrotyphlops punctatus Typhlops vermicularis Typhlops arenarius Typhlops luzonensis 100 Typhlops ruber 76 Ramphotyphlops albiceps 84 Typhlops pammeces 100 Ramphotyphlops braminus 99 97 Typhlopidae sp. (Sri Lanka) Ramphotyphlops lineatus 65 Ramphotyphlops acuticaudus 72 Acutotyphlops subocularis 100 Acutotyphlops kunuaensis Ramphotyphlops polygrammicus Austrotyphlops diversus 74 91 Austrotyphlops howi 75 87 Austrotyphlops guentheri Austrotyphlops bituberculatus 100 Austrotyphlops grypus Austrotyphlops longissimus 100 52 Austrotyphlops leptosomus Austrotyphlops unguirostris 59 98 Austrotyphlops ammodytes 92 Austrotyphlops kimberleyensis 96 Austrotyphlops troglodytes 93 Austrotyphlops ganei 87 Austrotyphlops ligatus 76 Ramphotyphlops bicolor 96 Austrotyphlops pinguis 90 Austrotyphlops splendidus 99 Austrotyphlops waitii Austrotyphlops australis 98 81 Austrotyphlops endoterus Austrotyphlops hamatus 74 91 Austrotyphlops pilbarensis 100 90 S Leptotyphlopidae Gerrhopilidae Xenotyphlopidae Typhlopidae 100 Anomalepididae T-AA Figure 20 Species-level squamate phylogeny continued (S). Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 25 of 53 98 100 97 T U-AA Figure 21 Species-level squamate phylogeny continued (T). Anilius scytale Aniliidae Trachyboa gularis Trachyboa boulengeri 100 Tropidophis pardalis 100 Tropidophis wrighti Tropidophiidae Tropidophis greenwayi 100 100 Tropidophis haetianus 53 Tropidophis feicki 98 Tropidophis melanurus Xenophidiidae Xenophidion schaeferi Casarea dussumieri Bolyeriidae Sanzinia madagascariensis 100 Sanziniinae Acrantophis madagascariensis 100 100 Acrantophis dumerili Calabariidae Calabaria reinhardtii Exiliboa placata 100 Ungaliophis continentalis Ungaliophiinae 99 Charina bottae 100 Lichanura trivirgata Candoia aspera 100 Candoia carinata Candoiinae 99 81 Candoia bibroni Eryx jayakari 69 Eryx colubrinus 100 53 Eryx conicus 87 Eryx johnii Erycinae 95 87 Eryx jaculus Eryx elegans 96 Boidae Eryx miliaris 93 83 100 Eryx tataricus Boa constrictor Corallus hortulanus 99 Corallus caninus 98 Corallus annulatus Epicrates cenchria 88 100 100 Eunectes murinus Eunectes notaeus Epicrates angulifer Boinae 96 94 Epicrates inornatus 85 Epicrates monensis Epicrates fordi 90 Epicrates subflavus Epicrates chrysogaster 95 100 Epicrates exsul 92 Epicrates striatus Anomochilidae Anomochilus leonardi 65 Cylindrophis maculatus Cylindrophiidae 100 Cylindrophis ruffus Melanophidium punctatum Brachyophidium rhodogaster 98 Uropeltis liura 86 Uropeltis ceylanicus 90 Rhinophis travancoricus 73 100 Uropeltis melanogaster Uropeltis phillipsi 80 Uropeltidae Rhinophis drummondhayi 82 89 69 Rhinophis dorsimaculatus Rhinophis philippinus 77 Rhinophis oxyrhynchus Pseudotyphlops philippinus 84 Rhinophis homolepis 85 80 Rhinophis blythii Xenopeltis unicolor Xenopeltidae Loxocemus bicolor Loxocemidae Python brongersmai 98 99 Python regius 99 Python curtus 86 100 96 Python sebae Python molurus 98 Broghammerus reticulatus 100 Broghammerus timoriensis Morelia oenpelliensis 76 Morelia boeleni 97 Morelia amethistina 100 100 Aspidites ramsayi Aspidites melanocephalus 75 Liasis olivaceus Pythonidae Apodora papuana 98 Liasis mackloti 96 100 Liasis fuscus Leiopython albertisii 100 Bothrochilus boa Morelia viridis 71 Morelia carinata 84 96 100 Morelia spilota Morelia bredli 85 Antaresia maculosa Antaresia perthensis 51 Antaresia stimsoni 83 100 Antaresia childreni 100 Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Acrochordidae Acrochordus javanicus 95 100 Xenodermus javanicus 100 Achalinus meiguensis 98 Achalinus rufescens Asthenodipsas vertebralis 99 Aplopeltura boa Pareatidae Pareas monticola Pareas boulengeri 100 96 Pareas formosensis Pareas margaritophorus 95 91 Pareas macularius Pareas hamptoni Pareas carinatus 100 Pareas nuchalis 100 Eristicophis macmahoni 100 Pseudocerastes persicus 99 (i) Pseudocerastes fieldi Macrovipera lebetina 100 100 Macrovipera schweizeri 100 100 Montivipera xanthina Montivipera raddei 99 Montivipera bornmuelleri 94 Montivipera albizona 83 Montivipera wagneri 88 Daboia palaestinae 96 Daboia russelii 59 Macrovipera deserti 100 Macrovipera mauritanica 95 Vipera ammodytes 100 100 Vipera seoanei 93 Vipera nikolskii 100 Vipera berus 77 100 Vipera latastei Vipera aspis Vipera barani 99 Vipera kaznakovi Viperinae 100 Vipera eriwanensis 97 99 Vipera ursinii Vipera dinniki 85 59 Vipera renardi 80 Vipera lotievi Proatheris superciliaris Cerastes vipera 100 Cerastes cerastes 100 86 Cerastes gasperettii Causus resimus Causus rhombeatus 100 Causus defilippii 89 Echis carinatus 100 100 Echis omanensis 100 Echis coloratus 62 (i) 97 91 Viperidae 100 (ii) Echis ocellatus Echis jogeri Echis leucogaster 100 Echis pyramidum Atheris ceratophora 93 Atheris barbouri 100 Atheris chlorechis 51 Atheris hispida 100 Atheris squamigera 77 Atheris nitschei 53 94 Atheris desaixi Bitis worthingtoni 63 Bitis arietans Bitis nasicornis 100 Bitis gabonica 95 100 100 96 Bitis peringueyi Bitis caudalis 98 U Bitis xeropaga 99 V-AA 98 100 Bitis atropos Bitis cornuta Bitis rubida Figure 22 Species-level squamate phylogeny continued (U). 100 99 100 Azemiopinae Calloselasma rhodostoma Hypnale nepa Hypnale hypnale Hypnale zara Trimeresurus puniceus Trimeresurus borneensis 98 Trimeresurus malabaricus Trimeresurus gramineus 96 100 Trimeresurus trigonocephalus 100 Trimeresurus hageni 99 Trimeresurus malcolmi Trimeresurus flavomaculatus 99 Trimeresurus schultzei 89 Trimeresurus sumatranus 97 Trimeresurus popeiorum 89 98 Trimeresurus tibetanus Trimeresurus medoensis 94 Trimeresurus yunnanensis Trimeresurus gumprechti 81 Trimeresurus stejnegeri 72 96 Trimeresurus vogeli Trimeresurus kanburiensis 100 93 Trimeresurus venustus Trimeresurus macrops Trimeresurus fasciatus 96 64 Trimeresurus insularis 85 Trimeresurus septentrionalis 100 Trimeresurus andersonii Trimeresurus albolabris 93 Trimeresurus cantori 77 Trimeresurus erythrurus 100 Trimeresurus purpureomaculatus 99 97 Ovophis monticola 100 Ovophis zayuensis Ovophis tonkinensis 98 97 Protobothrops kaulbacki Protobothrops sieversorum Protobothrops mangshanensis Protobothrops cornutus 99 92 Protobothrops xiangchengensis 100 90 Protobothrops jerdonii Protobothrops elegans 100 100 Protobothrops mucrosquamatus Protobothrops flavoviridis 100 63 Protobothrops tokarensis 100 Ovophis okinavensis Trimeresurus gracilis Gloydius tsushimaensis 85 100 Gloydius brevicaudus 100 99 Gloydius ussuriensis Gloydius blomhoffii 100 Gloydius strauchi Gloydius halys 97 96 Gloydius shedaoensis 100 Gloydius intermedius 99 95 Gloydius saxatilis Atropoides occiduus 100 Atropoides nummifer 100 Atropoides olmec 99 Atropoides picadoi Cerrophidion godmani Cerrophidion tzotzilorum 94 90 Cerrophidion petlalcalensis 99 Porthidium ophryomegas 78 Porthidium dunni 96 Porthidium yucatanicum 100 Porthidium nasutum 100 Porthidium porrasi 86 Porthidium lansbergii 90 Bothrocophias campbelli Bothrocophias microphthalmus 99 Bothrocophias hyoprora Bothrops pictus Rhinocerophis ammodytoides 100 96 100 Rhinocerophis cotiara Rhinocerophis fonsecai Rhinocerophis alternatus 90 94 Rhinocerophis itapetiningae 99 Bothropoides erythromelas 100 Bothropoides diporus 100 Bothropoides neuwiedi 91 94 Bothropoides jararaca 100 Bothropoides insularis 90 Bothropoides alcatraz Bothriopsis pulchra 100 99 Bothriopsis chloromelas Bothriopsis taeniata 98 Bothriopsis bilineata 95 Bothrops brazili 100 Bothrops jararacussu 100 Bothrops punctatus 100 97 Bothrops caribbaeus Bothrops lanceolatus Bothrops asper 100 87 Bothrops marajoensis 90 Bothrops colombiensis Bothrops atrox 99 Bothrops moojeni 72 Bothrops leucurus Ophryacus undulatus 100 Mixcoatlus barbouri Mixcoatlus melanurus 85 100 100 Lachesis stenophrys Lachesis muta Bothriechis schlegelii 53 51 Bothriechis nigroviridis Bothriechis lateralis 98 Bothriechis marchi 98 100 100 Bothriechis thalassinus Bothriechis bicolor Bothriechis aurifer 91 Bothriechis rowleyi 84 Agkistrodon contortrix 100 Agkistrodon piscivorus Agkistrodon taylori 99 Agkistrodon bilineatus 99 Sistrurus catenatus Sistrurus miliarius 97 96 Crotalus pricei Crotalus intermedius 100 100 Crotalus transversus 98 Crotalus tancitarensis 100 52 Crotalus triseriatus 100 Crotalus pusillus Crotalus lepidus 87 Crotalus aquilus 95 74 Crotalus enyo 56 Crotalus polystictus Crotalus cerastes 99 Crotalus ravus 63 Crotalus willardi Crotalus horridus 97 100 Crotalus durissus 82 Crotalus simus Crotalus basiliscus 100 Crotalus molossus 100 Crotalus totonacus 91 Crotalus ruber 99 Crotalus catalinensis Crotalus atrox 100 100 Crotalus tortugensis Crotalus scutulatus 98 100 Crotalus oreganus Crotalus viridis 58 77 Crotalus mitchellii Crotalus tigris 89 Crotalus adamanteus 90 100 (ii) Crotalinae Stoliczkia borneensis Xenodermatidae 50 Acrochordus arafurae 97 Azemiops feae Garthius chaseni Tropidolaemus wagleri Deinagkistrodon acutus 91 Acrochordus granulatus 100 95 Page 26 of 53 95 Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 27 of 53 Enhydris chinensis Enhydris plumbea Enhydris matannensis 100 Enhydris enhydris Enhydris jagorii 100 Enhydris longicauda 100 100 Enhydris innominata 100 Myron richardsonii 100 Pseudoferania polylepis 71 Erpeton tentaculatum Enhydris bocourti 89 Bitia hydroides 96 Cantoria violacea 85 Gerarda prevostiana 70 Fordonia leucobalia 98 88 Enhydris punctata Homalopsis buccata 88 Cerberus australis 97 Cerberus microlepis 100 100 Cerberus rynchops Micrelaps bicoloratus Oxyrhabdium leporinum Prosymna ruspolii 100 Prosymna visseri 86 Prosymna janii Prosymna greigerti 100 Prosymna meleagris 99 Rhamphiophis oxyrhynchus 95 99 Rhamphiophis rubropunctatus Malpolon monspessulanus 96 Rhagerhis moilensis 54 Mimophis mahfalensis Dipsina multimaculata 97 Hemirhagerrhis viperina 100 Hemirhagerrhis kelleri 100 Hemirhagerrhis hildebrandtii Psammophylax acutus 65 Psammophylax rhombeatus 97 Psammophylax variabilis 100 Psammophylax tritaeniatus 90 95 Psammophis crucifer 70 Psammophis lineolatus Psammophis condanarus 100 Psammophis trigrammus Psammophis jallae 100 100 Psammophis leightoni 85 50 Psammophis notostictus Psammophis angolensis 100 Psammophis schokari 76 Psammophis punctulatus 80 Psammophis praeornatus 100 Psammophis tanganicus 69 Psammophis biseriatus Psammophis lineatus 96 95 Psammophis subtaeniatus 97 Psammophis sudanensis 73 Psammophis orientalis 60 Psammophis rukwae 100 Psammophis sibilans 80 Psammophis leopardinus 71 100 Psammophis mossambicus 100 Psammophis phillipsi Homoroselaps lacteus Atractaspis irregularis 98 Atractaspis microlepidota Atractaspis boulengeri 96 Atractaspis bibronii 98 Atractaspis micropholis 58 100 Atractaspis corpulenta 99 Macrelaps microlepidotus 96 Amblyodipsas polylepis Xenocalamus transvaalensis 100 Amblyodipsas dimidiata 94 Polemon notatus 97 Polemon collaris 100 Polemon acanthias 93 Aparallactus modestus 54 Aparallactus werneri 100 100 Aparallactus capensis 92 Aparallactus guentheri 100 Pythonodipsas carinata Pseudaspis cana 96 95 Psammodynastes pulverulentus Psammodynastes pictus 100 64 Buhoma procterae Buhoma depressiceps 92 Lycophidion nigromaculatum 100 Lycophidion laterale Lycophidion capense 69 Lycophidion ornatum 92 97 Hormonotus modestus Inyoka swazicus Gonionotophis stenophthalmus 93 Gonionotophis nyassae 100 Gonionotophis brussauxi 100 Gonionotophis poensis Gonionotophis capensis 100 Pseudoboodon lemniscatus Bothrolycus ater 97 Bothrophthalmus brunneus 92 Bothrophthalmus lineatus 100 Boaedon virgatus Boaedon lineatus 98 100 Boaedon fuliginosus 100 Boaedon olivaceus Lamprophis guttatus 95 Lamprophis fuscus 99 Lamprophis aurora 95 Lamprophis fiskii Lycodonomorphus inornatus Lycodonomorphus rufulus 90 Lycodonomorphus laevissimus 100 Lycodonomorphus whytii 98 99 Amplorhinus multimaculatus 100 Duberria variegata 82 Duberria lutrix Ditypophis vivax 99 Compsophis boulengeri 98 Compsophis albiventris Compsophis laphystius 100 Compsophis infralineatus 94 Alluaudina bellyi Parastenophis betsileanus Leioheterodon geayi 100 100 Leioheterodon madagascariensis Leioheterodon modestus 100 Langaha madagascariensis 90 100 Micropisthodon ochraceus Ithycyphus miniatus Ithycyphus oursi 100 100 Madagascarophis colubrinus 97 Madagascarophis meridionalis Lycodryas inornatus 94 Lycodryas citrinus 100 Lycodryas sanctijohannis 98 95 Lycodryas inopinae 100 Lycodryas pseudogranuliceps 54 Lycodryas granuliceps 100 Dromicodryas quadrilineatus Dromicodryas bernieri 98 Thamnosophis infrasignatus 95 Thamnosophis martae 93 Thamnosophis epistibes 100 98 Thamnosophis stumpffi Thamnosophis lateralis 95 Pseudoxyrhopus ambreensis 76 94 Heteroliodon occipitalis Liopholidophis dimorphus Liopholidophis dolicocercus 98 Liopholidophis sexlineatus 100 99 Liophidium rhodogaster Liophidium vaillanti 100 Liophidium therezieni 99 Liophidium torquatum 99 89 Liophidium mayottensis Liophidium chabaudi 73 97 53 Homalopsidae 58 Prosymninae Psammophiinae Lamprophiidae 98 Atractaspidinae Aparallactinae Pseudaspidinae 100 Lamprophiinae Pseudoxyrhophiinae V X-AA W Figure 23 Species-level squamate phylogeny continued (V). Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 28 of 53 Calliophis melanurus Maticora bivirgata Micruroides euryxanthus Sinomicrurus japonicus Sinomicrurus kelloggi 100 Sinomicrurus macclellandi 95 85 Micrurus corallinus Micrurus albicinctus 100 Micrurus psyches 90 Micrurus fulvius Micrurus diastema 99 100 Micrurus narduccii 98 Micrurus mipartitus Micrurus dissoleucus Micrurus surinamensis 91 Micrurus hemprichii 97 Micrurus lemniscatus Micrurus decoratus Micrurus baliocoryphus 94 Micrurus pyrrhocryptus 97 Micrurus altirostris 98 Micrurus ibiboboca 88 Micrurus spixii Micrurus frontalis 98 89 59 Micrurus brasiliensis Hemibungarus calligaster 84 Ophiophagus hannah 100 Dendroaspis angusticeps 84 Dendroaspis polylepis 87 63 Walterinnesia aegyptia Aspidelaps scutatus Hemachatus haemachatus Naja kaouthia 100 Naja atra 100 Naja naja Naja mandalayensis 91 Naja siamensis 99 Naja sumatrana 87 Naja multifasciata 69 90 Naja melanoleuca Naja annulata 58 100 Naja nivea 83 Naja annulifera 88 Naja haje 95 78 Naja nubiae 92 Naja pallida Naja katiensis 99 Naja mossambica 96 Naja nigricollis 96 Naja ashei 76 100 Elapsoidea nigra 99 Elapsoidea semiannulata Elapsoidea sundevallii Bungarus flaviceps Bungarus bungaroides 98 Bungarus fasciatus Bungarus sindanus 90 Bungarus ceylonicus 100 97 Bungarus caeruleus 97 100 Bungarus niger 100 Bungarus multicinctus 99 Bungarus candidus Laticauda laticaudata Laticauda saintgironsi 100 Laticauda guineai 98 100 Laticauda colubrina Micropechis ikaheka Toxicocalamus preussi 100 Demansia vestigiata 100 Demansia papuensis 100 Demansia psammophis 91 Toxicocalamus loriae 100 82 Furina ornata 92 Furina diadema Simoselaps semifasciatus 99 100 Simoselaps anomalus Simoselaps bertholdi 100 Aspidomorphus schlegeli 85 Aspidomorphus lineaticollis 68 Aspidomorphus muelleri 100 Acanthophis praelongus Acanthophis antarcticus Pseudechis porphyriacus 67 Pseudechis butleri 100 Pseudechis australis 100 100 100 Pseudechis colletti Pseudechis papuanus Pseudechis guttatus Cacophis squamulosus 89 Elapognathus coronata 88 88 Cryptophis nigrescens Rhinoplocephalus bicolor 95 98 Suta fasciata Suta monachus 100 Suta suta 90 Suta spectabilis 94 Vermicella intermedia Simoselaps calonotus 75 71 Denisonia devisi 100 Oxyuranus microlepidotus Oxyuranus scutellatus 100 97 Pseudonaja modesta Pseudonaja textilis Echiopsis curta 100 78 Drysdalia mastersii Drysdalia coronoides 100 Austrelaps labialis 97 Austrelaps superbus 98 Hoplocephalus bitorquatus 98 Echiopsis atriceps 99 Notechis scutatus 99 98 Tropidechis carinatus 100 Hemiaspis signata Hemiaspis damelii Emydocephalus annulatus 100 Aipysurus eydouxii 97 Aipysurus duboisii 91 94 Aipysurus apraefrontalis Aipysurus fuscus 90 100 Aipysurus laevis 100 96 Parahydrophis mertoni Ephalophis greyae Hydrelaps darwiniensis 98 Hydrophis elegans Hydrophis lapemoides 72 Hydrophis spiralis 94 94 Hydrophis semperi 100 100 Hydrophis pacifica 97 Hydrophis cyanocincta Hydrophis melanocephala 95 100 75 Hydrophis parviceps Hydrophis curtus Hydrophis platura Hydrophis stokesii Hydrophis atriceps 98 Hydrophis brooki 67 54 Hydrophis caerulescens Hydrophis czeblukovi 83 83 Hydrophis major 77 Hydrophis schistosa 93 Hydrophis macdowelli Hydrophis kingii 88 Hydrophis peronii 74 100 Hydrophis ornata 61 100 Elapidae W Figure 24 Species-level squamate phylogeny continued (W). Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 29 of 53 Calamariinae Pseudorabdion oxycephalum Calamaria pavimentata Calamaria yunnanensis Plagiopholis styani 100 Pseudoxenodon bambusicola 97 Pseudoxenodon macrops 85 Pseudoxenodon karlschmidti Scaphiodontophis annulatus 96 Sibynophis bistrigatus 100 Sibynophis subpunctatus 68 Sibynophis triangularis Sibynophis collaris 100 Sibynophis chinensis 100 Grayia tholloni 100 Grayia ornata Grayia smithii Ahaetulla fronticincta Ahaetulla pulverulenta 100 Ahaetulla nasuta 100 Chrysopelea taprobanica 100 Chrysopelea ornata 100 Chrysopelea paradisi 69 Dendrelaphis bifrenalis Dendrelaphis caudolineolatus Dendrelaphis caudolineatus 100 Dendrelaphis schokari 97 Dendrelaphis tristis 91 Boiga kraepelini 71 Crotaphopeltis tornieri 99 73 Dipsadoboa unicolor Telescopus fallax 89 Boiga irregularis 96 Boiga dendrophila Boiga forsteni 96 100 Boiga cynodon 68 Boiga barnesii 100 85 Boiga trigonata Boiga ceylonensis Boiga beddomei 74 Boiga multomaculata 79 Toxicodryas pulverulenta Dasypeltis confusa Dasypeltis atra 98 Dasypeltis scabra 70 Dasypeltis sahelensis 92 Dasypeltis gansi 77 Dasypeltis fasciata 90 Scaphiophis albopunctatus Oligodon arnensis 100 Oligodon sublineatus 86 Oligodon taeniolatus 83 Oligodon octolineatus Oligodon cyclurus 85 Oligodon barroni 100 100 Oligodon taeniatus 99 89 Oligodon chinensis 100 Oligodon ocellatus 99 Oligodon formosanus 90 99 Oligodon cinereus 93 Oligodon maculatus Oligodon splendidus 56 97 Oligodon cruentatus 98 Oligodon theobaldi 100 Oligodon torquatus 98 Oligodon planiceps Coelognathus radiatus 100 Coelognathus helena Coelognathus erythrurus 100 99 Coelognathus subradiatus Coelognathus flavolineatus Thrasops jacksonii 90 Dispholidus typus 98 Thelotornis capensis 52 Philothamnus carinatus Philothamnus heterodermus 60 Philothamnus nitidus 94 Philothamnus semivariegatus 90 57 88 Philothamnus angolensis 99 Philothamnus girardi Philothamnus thomensis 68 99 Philothamnus natalensis 69 Philothamnus hoplogaster Hapsidophrys lineatus 87 99 Hapsidophrys smaragdina 68 Hapsidophrys principis Lytorhynchus diadema Coluber zebrinus 92 Bamanophis dorri 86 100 Macroprotodon cucullatus 100 Macroprotodon abubakeri Hemerophis socotrae 100 Hemorrhois hippocrepis 94 100 Hemorrhois algirus Hemorrhois nummifer 100 Hemorrhois ravergieri 99 Spalerosophis microlepis 60 Spalerosophis diadema 95 86 Platyceps rhodorachis 100 Platyceps rogersi Platyceps karelini 100 61 Platyceps ventromaculatus Platyceps najadum 94 100 98 Platyceps collaris Platyceps florulentus 52 Dolichophis jugularis 100 Dolichophis schmidti 100 Dolichophis caspius 100 Hierophis viridiflavus 100 Hierophis gemonensis Hierophis spinalis 92 100 Eirenis modestus 83 Eirenis aurolineatus Eirenis persicus 100 Eirenis decemlineatus Eirenis levantinus 86 Eirenis medus 83 82 Eirenis thospitis Eirenis lineomaculatus 97 86 Eirenis rothii 59 Eirenis coronelloides Eirenis eiselti 100 Eirenis collaris Eirenis barani 91 Eirenis punctatolineatus 100 99 97 Pseudoxenodontinae Sibynophiinae Grayiinae 74 71 68 X Z-AA Figure 25 Species-level squamate phylogeny continued (X). Colubrinae Colubridae 100 Y Colubrinae cont. Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 30 of 53 Cyclophiops major Ptyas korros Ptyas mucosa Oxybelis fulgidus 82 Oxybelis aeneus 96 100 Opheodrys vernalis Opheodrys aestivus Salvadora mexicana 93 Tantilla melanocephala 93 Coluber taeniatus Coluber constrictor 88 Coluber flagellum 92 Chironius quadricarinatus Chironius carinatus Leptophis ahaetulla 97 Dendrophidion dendrophis 92 93 Dendrophidion percarinatum 99 66 Drymobius rhombifer Trimorphodon biscutatus 91 Phyllorhynchus decurtatus 82 Spilotes pullatus 98 Pseustes sulphureus Drymarchon corais 100 Chironius fuscus Chironius scurrulus Chironius laevicollis 87 Chironius grandisquamis 74 Chironius flavolineatus 86 Chironius bicarinatus Chironius monticola 81 Chironius exoletus 83 Chironius laurenti 54 99 Chironius multiventris 100 Drymoluber dichrous 100 Drymoluber brazili 92 Mastigodryas melanolomus 64 87 Mastigodryas boddaerti Mastigodryas bifossatus Rhinobothryum lentiginosum 71 87 Stenorrhina freminvillei Chionactis occipitalis Chilomeniscus stramineus 89 Sonora semiannulata 94 99 Conopsis biserialis Conopsis nasus Ficimia streckeri 100 Gyalopion canum Pseudoficimia frontalis Sympholis lippiens 100 Gonyosoma oxycephalum 98 Gonyosoma jansenii Rhadinophis prasinus 100 100 Rhynchophis boulengeri 53 Rhadinophis frenatus Lycodon ruhstrati Lycodon laoensis 86 Lycodon fasciatus 83 Lycodon paucifasciatus 92 Lycodon rufozonatum 93 60 Lycodon semicarinatum Dryocalamus nympha Lycodon carinatus 83 Lycodon capucinus 94 98 76 Lycodon osmanhilli Lycodon zawi Lycodon aulicus Archelaphe bella 100 Euprepiophis conspicillata Euprepiophis mandarinus 100 Oreocryptophis porphyraceus Orthriophis taeniurus 99 Orthriophis hodgsoni Orthriophis moellendorffi 88 98 Orthriophis cantoris Zamenis hohenackeri 99 Zamenis persicus 100 Zamenis longissimus 99 64 Zamenis lineatus Rhinechis scalaris 100 100 Zamenis situla Elaphe davidi Elaphe carinata 93 Elaphe bimaculata 90 100 100 Elaphe dione 61 Elaphe climacophora 55 Elaphe schrenckii Elaphe quadrivirgata 100 83 Elaphe quatuorlineata Elaphe sauromates 75 Coronella girondica 98 Coronella austriaca 83 Oocatochus rufodorsatus Senticolis triaspis Pituophis deppei 100 Pituophis vertebralis 84 Pituophis lineaticollis 91 Pituophis melanoleucus Pituophis ruthveni 94 100 99 Pituophis catenifer 98 Pantherophis vulpinus Pantherophis guttatus 100 Pantherophis emoryi 99 Pantherophis slowinskii 96 Pantherophis spiloides 100 Pantherophis alleghaniensis 100 100 98 Pantherophis obsoletus Pantherophis bairdi 100 Bogertophis subocularis Bogertophis rosaliae Rhinocheilus lecontei 98 87 Arizona elegans Pseudelaphe flavirufa Cemophora coccinea Lampropeltis calligaster 100 Lampropeltis webbi Lampropeltis pyromelana 100 75 Lampropeltis zonata 92 Lampropeltis elapsoides 72 Lampropeltis mexicana 79 94 82 Lampropeltis ruthveni Lampropeltis triangulum Lampropeltis extenuatum 100 Lampropeltis alterna 96 98 Lampropeltis nigra 74 Lampropeltis getula 96 Lampropeltis holbrooki Lampropeltis splendida 60 98 Lampropeltis californiae 100 81 Colubrinae cont. Y Figure 26 Species-level squamate phylogeny continued (Y). Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 31 of 53 Trachischium monticola Amphiesma sauteri 100 Amphiesma craspedogaster 99 Natriciteres olivacea 98 Afronatrix anoscopus Lycognathophis seychellensis Macropisthodon rudis 68 Balanophis ceylonensis 100 Rhabdophis subminiatus 69 Rhabdophis tigrinus 62 96 Rhabdophis nuchalis 98 88 Amphiesma stolatum Xenochrophis vittatus Xenochrophis flavipunctatus Natricinae Xenochrophis piscator 100 Atretium schistosum 100 Xenochrophis punctulatus Xenochrophis asperrimus 88 Atretium yunnanensis 100 Aspidura drummondhayi 100 Aspidura trachyprocta Aspidura ceylonensis 99 Aspidura guentheri Opisthotropis guangxiensis 100 Opisthotropis lateralis Opisthotropis latouchii 86 100 Opisthotropis cheni Sinonatrix aequifasciata 100 98 Sinonatrix percarinata 82 Sinonatrix annularis Natrix maura 100 Natrix natrix 88 Natrix tessellata Clonophis kirtlandii Virginia striatula 72 100 Storeria occipitomaculata 98 97 Storeria dekayi Seminatrix pygaea 80 Regina rigida 100 100 Regina alleni Regina septemvittata 76 Regina grahami 50 Tropidoclonion lineatum 96 100 Nerodia cyclopion Nerodia floridana 100 100 Nerodia taxispilota Nerodia rhombifer Nerodia erythrogaster 99 Nerodia harteri Nerodia fasciata 100 100 Nerodia sipedon Thamnophis sirtalis 69 Thamnophis sauritus 100 Thamnophis proximus Thamnophis rufipunctatus 93 Adelophis foxi Thamnophis valida 100 Thamnophis melanogaster 100 Thamnophis exsul 72 Thamnophis godmani 85 Thamnophis scaliger 96 100 Thamnophis sumichrasti 98 Thamnophis mendax Thamnophis fulvus 100 Thamnophis chrysocephalus Thamnophis cyrtopsis 86 Thamnophis eques 99 99 Thamnophis marcianus Thamnophis hammondii 100 Thamnophis ordinoides 92 99Thamnophis couchii 63 69 Thamnophis atratus Thamnophis gigas 73 Thamnophis elegans Thamnophis brachystoma 94 100 Thamnophis radix 89 Thamnophis butleri 99 Z Figure 27 Species-level squamate phylogeny continued (Z). Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 32 of 53 Conophis lineatus Crisantophis nevermanni Psomophis obtusus 94 Psomophis genimaculatus Psomophis joberti Contia tenuis 100 Pseudalsophis biserialis 72 Pseudalsophis elegans Heterodon platirhinos Arrhyton taeniatum 100 100 Arrhyton supernum Heterodon simus Arrhyton vittatum 58 Arrhyton landoi 99 Heterodon nasicus 73 Arrhyton procerum Arrhyton tanyplectum 91 75 100 Diadophis punctatus 98 Arrhyton dolichura Magliophis exiguum 81 100 Carphophis amoenus Cubophis cantherigerus 87 100 Cubophis vudii Farancia abacura Caraiba andreae 99 80 Haitiophis anomalus 93 98 Borikenophis portoricensis Farancia erytrogramma 80 Alsophis antillensis 100 Alsophis rijgersmaei Nothopsis rugosus 97 Alsophis antiguae 97 Amastridium veliferum 100 Alsophis rufiventris 68 99 Ialtris dorsalis Darlingtonia haetiana Tantalophis discolor 89 100 99 Hypsirhynchus ferox 83 Antillophis parvifrons Coniophanes fissidens Schwartzophis callilaemum 98 Schwartzophis polylepis Rhadinaea flavilata 100 96 93 100 Schwartzophis funereum 86 Uromacer catesbyi 100 Rhadinaea fulvivittis Uromacer oxyrhynchus Uromacer frenatus 99 Pseudoleptodeira latifasciata Lygophis anomalus Lygophis elegantissimus 100 80 Trimetopon gracile Lygophis lineatus 99 99 Lygophis paucidens Hypsiglena slevini 76 78 Lygophis flavifrenatus 73 Lygophis meridionalis 70 Hypsiglena jani Xenodon severus Xenodon merremi 63 98 Hypsiglena affinis 100 100 Xenodon werneri 52 100 Xenodon neuwiedii Hypsiglena ochrorhyncha 98 99 Xenodon dorbignyi Xenodon histricus 75 Hypsiglena torquata 84 Xenodon nattereri 99 Xenodon guentheri 85 71 Hypsiglena chlorophaea Xenodon semicinctus 61 98 90 Xenodon matogrossensis 94 Tretanorhinus variabilis 62 Xenodon pulcher Eryrthrolamprus atraventer 92 nigrofasciata Leptodeira Eryrthrolamprus jaegeri 64 Eryrthrolamprus almadensis 73 Imantodes inornatus Eryrthrolamprus ceii 71 99 89 100 Eryrthrolamprus poecilogyrus Imantodes lentiferus Eryrthrolamprus epinephelus Eryrthrolamprus juliae 67 87 94 Imantodes gemmistratus Eryrthrolamprus miliaris 100 Eryrthrolamprus reginae 96 86 Imantodes cenchoa Eryrthrolamprus breviceps 88 Eryrthrolamprus pygmaea Leptodeira uribei Eryrthrolamprus typhlus 97 Erythrolamprus mimus 87 100 Leptodeira frenata Erythrolamprus aesculapii 100 51 Philodryas baroni Philodryas nattereri Leptodeira splendida 100 88 Philodryas viridissima 100 Philodryas olfersii Leptodeira punctata Philodryas argentea 68 Philodryas georgeboulengeri Leptodeira septentrionalis 100 91 Philodryas mattogrossensis 90 68 Philodryas psammophidea 96 Leptodeira annulata 98 Philodryas aestiva 97 Philodryas agassizii 62 Leptodeira bakeri Philodryas patagoniensis 94 88 Sordellina punctata Leptodeira maculata 95 Taeniophallus brevirostris 100 Taeniophallus nicagus 100 Leptodeira rubricata Echinanthera melanostigma 66 Echinanthera undulata Adelphicos quadrivirgatum 67 Taeniophallus affinis 75 79 90 Phalotris lemniscatus 95 Hydromorphus concolor Phalotris nasutus 100 Phalotris lativittatus 100 Tretanorhinus nigroluteus Phalotris mertensi 100 100 Elapomorphus quinquelineatus Cryophis hallbergi 100 Apostolepis assimilis 56 Apostolepis dimidiata Geophis carinosus 95 Apostolepis albicollaris 91 97 Apostolepis flavotorquata 94 Geophis godmani 94 Apostolepis sanctaeritae 69 Apostolepis cearensis 99 Atractus zidoki Manolepis putnami 55 Hydrops triangularis Atractus wagleri Pseudoeryx plicatilis 86 83 Helicops infrataeniatus 100 Atractus schach Helicops hagmanni 68 91 98 Helicops carinicaudus Atractus albuquerquei 99 Helicops gomesi 96 91 68 Helicops angulatus Atractus elaps Gomesophis brasiliensis Calamodontophis paucidens 97 73 Atractus flammigerus 89 Pseudotomodon trigonatus 100 Tachymenis peruviana 70 Atractus badius Ptychophis flavovirgatus 87 Tomodon dorsatus 86 75 Atractus reticulatus Thamnodynastes pallidus 94 90 Thamnodynastes lanei 90 Atractus trihedrurus 73 Thamnodynastes hypoconia 91 99 Thamnodynastes strigatus 93 97 Thamnodynastes rutilus Atractus zebrinus 100 Tropidodryas serra Tropidodryas striaticeps Ninia atrata 87 100 Xenopholis undulatus Xenopholis scalaris Sibon nebulatus 90 Caaeteboia amarali Hydrodynastes bicinctus 100 Tropidodipsas sartorii 56 Hydrodynastes gigas 100 Siphlophis cervinus Dipsas indica 68 98 91 Siphlophis compressus Siphlophis pulcher Dipsas catesbyi 84 100 Siphlophis longicaudatus Oxyrhopus petolarius Dipsas neivai 95 82 Oxyrhopus formosus 100 Dipsas variegata 100 Oxyrhopus trigeminus Oxyrhopus clathratus 67 Oxyrhopus rhombifer Dipsas pratti 63 70 Oxyrhopus melanogenys 95 95 Oxyrhopus guibei 67 Sibynomorphus mikanii Rodriguesophis iglesiasi 96 96 Paraphimophis rusticus Sibynomorphus turgidus Phimophis guerini 87 75 Clelia clelia 87 (i) Dipsas articulata Mussurana bicolor 96 Drepanoides anomalus 90 Dipsas albifrons 79 74 Boiruna maculata (ii) Rhachidelus brazili 92 Sibynomorphus ventrimaculatus 88 Pseudoboa neuwiedii Pseudoboa nigra 79 100 Sibynomorphus neuwiedi Pseudoboa coronata Thermophis zhaoermii 100 95 Thermophis baileyi 100 (ii) Dipsadinae (i) AA Figure 28 Species-level squamate phylogeny continued (AA). Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 need for considering these clades as families, since the family Scincidae is clearly monophyletic, based on our results and others (see above). Thus, their new taxonomy changes the long-standing definition of Scincidae unnecessarily (see [113]). Furthermore, these changes were done without defining the full content (beyond a type genus) of any of these families other than Scincidae (the former Scincinae + Feylininae) and Acontiidae (the former Acontiinae). Most importantly, the new taxonomy proposed by these authors [112] is at odds with the phylogeny estimated here, with respect to the familial and subfamilial classification of >1000 skink species (Figures 6, 7, 8, 9, 10). For instance, Sphenomorphus stellatus is found in a strongly supported clade containing Lygosoma (presumably Lygosomidae; Figure 10), which is separate from the other clade (presumably Sphenomorphidae) containing the other sampled Sphenomorphus species (Figure 7; note that these Sphenomorphus species are divided among several subclades within this latter clade). An additional problem is that Egernia, Lygosoma, and Sphenomorphus are the type genera of Egerniidae, Lygosomidae, and Sphenomorphidae, but are paraphyletic as currently defined (Figures 7, 8, 9, 10), leading to further uncertainty in the content and definition of these putative families. Furthermore, Mabuyidae apparently refers to the clade (Figure 9) containing Chioninia, Dasia, Mabuya, Trachylepis, with each of these genera placed in its own subfamily (Chioniniinae, Dasiinae, Mabuyinae, and Trachylepidinae). However, several other genera are strongly placed in this group, such as Eumecia, Eutropis, Lankaskincus, and Ristella (Figure 9). These other genera cannot be readily fit into these subfamilial groups (i.e. they are not the sister group of any genera in those subfamilies), and Trachylepis is paraphyletic with respect to Eumecia, Chioninia, and Mabuya (Figure 9). Also, we find that Emoia is divided between clades containing Lygosoma (Lygosomidae) and Eugongylus (Eugongylidae), and many of these relationships have strong support (Figure 10). Finally, Ateuchosaurus is apparently not accounted for in their classification, and here is weakly placed as the sister-group to a clade comprising their Sphenomorphidae, Egerniidae, Mabuyidae, and Lygosomidae (i.e. Lygosominae as recognized here; Figures 7, 8, 9, 10). These authors [112] argued that a more heavily subdivided classification for skinks may be desirable for facilitating future taxonomic revisions and species descriptions. However, this classification seems likely to only exacerbate existing taxonomic problems (e.g. placing congeneric species in different families without revising the genus-level taxonomy). Here, we retain the previous definition of Mabuya (restricted to the New World clade; sensu [114]), and we support the traditional Page 33 of 53 definitions of Scincidae, Acontiinae, Scincinae (but including Feylininae), and Lygosominae (Figures 6, 7, 8, 9, 10; note that we leave Ateuchosaurus as incertae sedis). The other taxonomic issues in Scincidae identified here and elsewhere should be resolved in future studies. Our phylogeny provides a framework in which these analyses can take place (i.e. identifying major subclades within skinks), which we think may be more useful than a classification lacking clear taxon definitions. Of the 133 scincid genera [1], we can assign the 113 sampled in our tree to one of the three subfamilies in our classification (Acontiinae, Lygosominae, and Scincinae; Appendix I). We place 19 of the remaining genera into one of the three subfamilies based on previous classifications (e.g. [110]), with Ateuchosaurus as incertae sedis in Scincidae. Below, we review the non-monophyletic genera in our tree. Many of these problems have been reported by previous authors [51,111,115-118], and for brevity we do not distinguish between cases reported in previous studies, and potentially new instances found here. Within Acontiinae, we find that the two genera are both monophyletic (Figure 6). Within Scincinae, many genera are now strongly monophyletic (thanks in part to the dismantling of Eumeces; [49,50,119]), but some problems remain (Figure 6). The genera Scincus and Scincopus are strongly supported as being nested inside of the remaining Eumeces. Among Malagasy scincines (see [49,120]), Pseudacontias is nested inside Madascincus, and the genera Androngo, Pygomeles, and Voeltzkowia are all nested in Amphiglossus (Figure 6). We also find numerous taxonomic problems within lygosomines (Figures 7, 8, 9, 10). Species of Sphenomorphus are widely dispersed among other lygosomine genera. The genus Tropidophorus is paraphyletic with respect to a clade containing many other genera (Figure 7). The sampled species of Asymblepharus are only distantly related to each other, including one species (A. sikimmensis) nested inside of Scincella (Figure 7). The genus Lipinia is polyphyletic, with one species (L. vittigera) strongly placed as the sister taxon to Isopachys, and with two other species (L. pulchella and L. noctua) placed in a well-supported clade that also includes Papuascincus (Figure 7). Among Australian skinks, the genus Eulamprus is polyphyletic with respect to Nangura, Calyptotis, Gnypetoscincus, Coggeria, Coeranoscincus, Ophioscincus, Saiphos, Anomalopus, Eremiascincus, Hemiergis, Glaphyromorphus, Notoscincus, Ctenotus, and Lerista, and most of the relevant nodes are strongly supported (Figure 8). The genera Coeranoscincus and Ophioscincus are polyphyletic with respect to each other and to Saiphos and Coggeria (Figure 8). The genus Glaphyromorphus is paraphyletic with respect to a clade of Eulamprus (Figure 8). The genus Egernia is paraphyletic with respect to Bellatorias (which is paraphyletic Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 with respect to Egernia and Lissolepis) and Lissolepis, although many of the relevant nodes are not strongly supported (Figure 9). The genera Cyclodomorphus and Tiliqua are paraphyletic with respect to each other (Figure 9). Among other lygosomines, Trachylepis is nonmonophyletic [121], with two species (T. aurata and T. vittata) that fall outside the strongly supported clade containing the other species (Figure 9). The latter clade is weakly supported as the sister group to a clade containing Chioninia, Eumecia, and Mabuya. In Mabuya, a few species (M. altamazonica, M. bistriata, and M. nigropuncata) have unorthodox placements within a monophyletic Mabuya, potentially due to uncertain taxonomic assignment of specimens by previous authors [51,122]. The genus Lygosoma is paraphyletic with respect to Lepidothyris and Mochlus, and many of the relevant nodes are strongly supported (Figure 10). Among New Caledonian skinks, the genus Lioscincus is polyphyletic with respect to Marmorosphax, Celatiscincus, and Tropidoscincus, and both Lioscincus and Tropidoscincus are paraphyletic with respect to, Kanakysaurus, Lacertoides, Phoboscincus, Sigaloseps, Tropidoscincus, Graciliscincus, Simiscincus, and Caledoniscincus, with strong support for most relevant nodes (Figure 10). The genera Emoia and Bassiana are massively polyphyletic and divided across multiple lygosomine clades (Figure 10). The genus Lygisaurus appears to be nested inside of Carlia, although many of the relevant branches are only weakly supported (Figure 10). Lacertoidea Within Lacertoidea (Figure 1), we corroborate recent molecular analyses (e.g. [16,17,19,20]) and morphologybased phylogenies and classifications (e.g. [13,15]) in supporting the clade including the New World families Gymnophthalmidae and Teiidae (Figure 11). Within a weakly supported Teiidae (Figure 11), the subfamilies Tupinambinae and Teiinae are each strongly supported as monophyletic, as in previous studies [61]. In Tupinambinae, Callopistes is the sister group to a clade containing Tupinambis, Dracaena, and Crocodilurus. The clade Dracaena + Crocodilurus is nested within Tupinambis, and the associated clades have strong support (Figure 11). We find that the teiine genera Ameiva and Cnemidophorus are non-monophyletic (Figure 11), interdigitating with each other and the monophyletic genera Aspidoscelis, Dicrodon (monotypic), and Kentropyx, as in previous phylogenies [62]. A recent study [123] proposed a re-classification of the family Teiidae based on analysis of 137 morphological characters for 101 terminal species (with ~150 species in the family [1]). Those authors erected several new genera and subfamilies in an attempt to deal with the apparent non-monophyly of currently recognized taxa in their Page 34 of 53 tree. However, in our tree, some of these new taxa conflict strongly with the phylogeny or are rendered unnecessary. First, they recognize Callopistinae as a distinct subfamily for Callopistes, arguing that failure to do so would produce a taxonomy inconsistent with teiid phylogeny. However, we find strong support for Callopistes in its traditional placement as part of Tupinambinae (Figure 11), and this change is thus not needed based on our results. The genus Ameiva is paraphyletic under traditional definitions [62]. In our tree, their conception of Ameiva is also non-monophyletic, with species found in three distinct clades (Figure 11). We also find non-monophyly of many of their species groups within Ameiva, including the ameiva, bifrontata, dorsalis, and erythrocephala groups (Figure 11). Their genera Aurivela (Cnemidophorus longicaudus) and Contomastyx (Cnemidophorus lacertoides) are strongly supported as sister taxa in our tree, and are nested within Ameiva in their erythrocephala species group, along with Dicrodon (Figure 11). On the positive side, many of the genera they recognize are monophyletic and are not nested in other genera in our tree, including their Ameivula (Cnemidophorus ocellifer), Aspidoscelis (unchanged from previous definitions), Cnemidophorus (excluding C. ocellifer, C. lacertoides, and C. longicaudus), Holcosus (Ameiva undulata, A. festiva, and A. quadrilineatus), Kentropyx (unchanged from previous definitions), Salvator (Tupinambis rufescens, T. duseni, and T. merianae), and Teius (unchanged from previous definitions). We did not sample Ameiva edracantha (their Medopheos). Given our results, major taxonomic rearrangements within Teiidae seem problematic at present, especially with the extensive paraphyly of many traditional and redefined teiid genera, the lack of strong resolution of many of these relationships based on molecular and morphological data, and incomplete taxon sampling in all studies so far. Thus, we provisionally retain the traditional taxonomy of Teiidae, pending additional data and analyses. However, we note that Ameiva, Cnemidophorus, and Tupinambis are clearly non-monophyletic based on both our results and those of recent authors [123], and will require taxonomic changes in the future. We anticipate that many of these newly proposed genera [123] will be useful in such revisions. We find strong support (SHL = 98) for monophyly of Gymnophthalmidae (Figure 11). Within Gymnophthalmidae, we find strong support for the monophyly of the previously recognized subfamilies [63,64,124], with the exception of Cercosaurinae (Figure 11). Previous researchers considered the genus Bachia a distinct tribe (Bachiini) within Cercosaurinae, based on a poorly supported sistergroup relationship with the tribe Cercosaurini [63,64]. Here, we find a moderately well supported relationship (SHL = 84) between Bachia and Gymnophthalminae + Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Rhachisaurinae, and we find that this clade is only distantly related to other Cercosaurinae. Therefore, we restrict Cercosaurinae to the tribe Cercosaurini, and elevate the tribe Bachiini [64] to the subfamily level. The subfamily Bachiinae contains only the genus Bachia (Figure 11), identical in content to the previously recognized tribe [64]. Within Cercosaurinae, we find that the genus Petracola is nested within Proctoporus (Figure 11). In Ecpleopinae, Leposoma is divided into two clades, separated by Anotosaura, Colobosauroides, and Arthrosaura (Figure 11), and many of the relevant nodes are very strongly supported. These issues should be addressed in future studies. Our results show strong support for a clade uniting Lacertidae and Amphisbaenia (Figure 1), as in many previous studies [16-20,23]. We also find strong support for monophyly of amphisbaenians (SHL = 99), in contrast to some molecular analyses [19,20]. Relationships among amphisbaenian families are generally strongly supported and similar to those in earlier molecular studies (Figure 12), including the placement of the New World family Rhineuridae as sister group to all other amphisbaenians [70,71,125]. The family Cadeidae is placed as the sister-group to Amphisbaenidae + Trogonophiidae (Figures 1 and Figure 12) with weak support, but has been placed with Blanidae in previous studies, with strong support but less- extensive taxon sampling [125,126]. We find strong support for monophyly of the Old World family Lacertidae (Figure 13). Within Lacertidae, branch support for the monophyly of most genera and for the subfamilies Gallotiinae and Lacertinae is very high (Figure 13). However, we find that relationships among many genera are poorly supported, as in previous studies [65,67,68]. Our results (Figure 13) also indicate that several lacertid genera are non-monophyletic with strong support for the associated nodes, including Algyroides (paraphyletic with respect to Dinarolacerta), Ichnotropis (paraphyletic with respect to Meroles), Meroles (paraphyletic with respect to Ichnotropis), Nucras (polyphyletic with respect to several genera, including Pedioplanis, Poromera, Latastia, Philocortus, Pseuderemias, and Heliobolus), and Pedioplanis (paraphyletic with respect to Nucras). Higher-level phylogeny of Toxicofera We find strong support (SHL = 96) for monophyly of Toxicofera (Anguimorpha, Iguania, and Serpentes; Figure 1), and moderate support for a sister-group relationship between Iguania and Anguimorpha (SHL = 79). Relationships among Anguimorpha, Iguania, and Serpentes were weakly supported in some Bayesian and likelihood analyses [16-19], but strongly supported in others [20]. We further corroborate previous studies in also placing Anguimorpha with Iguania [16-20]. In contrast, some other studies have placed Page 35 of 53 anguimorphs with snakes as the sister group to iguanians [127,128]. Anguimorpha Our hypothesis for family-level anguimorphan relationships (Figures 1, 14) is generally similar to that of other recent studies [17,19,20,129], and is strongly supported. Our results differ from some analyses based only on morphology, which place Anguidae near the base of Anguimorpha [130]. Here, Shinisauridae is strongly supported as the sister taxon to a well-supported clade of Varanidae + Lanthanotidae (Figures 1, 14). Varanid relationships are similar to previous estimates (e.g. [131]). Xenosauridae is here strongly supported as the sister-group to a strongly supported clade containing Helodermatidae and the strongly supported Anniellidae + Anguidae clade (Figures 1, 14). However, previous molecular analyses have placed Helodermatidae as the sister to Xenosauridae + (Anniellidae + Anguidae), typically with strong support [16,17,19,20]. Within Anguidae (Figure 14), our phylogeny indicates non-monophyly of genera within every subfamily, including Diploglossinae (Diploglossus and Celestus are strongly supported as paraphyletic with respect to each other and to Ophiodes), Anguinae (Ophisaurus is strongly supported as paraphyletic with respect to Anguis, Dopasia, and Pseudopus), and Gerrhonotinae (Abronia and Mesaspis are non-monophyletic, and Coloptychon is nested inside Gerrhonotus). Some of these problems were not reported previously (e.g. Coloptychon, Abronia, and Mesaspis), due to incomplete taxon sampling in previous studies [129,132,133], but relationships within Gerrhonotinae are under detailed investigation by other researchers, so these issues are likely to be resolved in the near future. Iguania We find strong support (SHL = 100) for the monophyly of Iguania (Figure 1). This clade is strongly supported by nuclear data [16,17,19,20], but an apparent episode of convergent molecular evolution in several mitochondrial genes has seemingly misled some analyses of mtDNA, leading to weak support for Iguania [134], or even separation of the acrodonts and pleurodonts [17,135] in previous studies. Within Iguania (Figure 1), we find strong support (SHL = 100) for a sister-group relationship between Chamaeleonidae and Agamidae (Acrodonta), and for a clade of mostly New World families (Pleurodonta; SHL = 100). We find strong support for the monophyly of Chamaeleonidae and the subfamily Chamaeleoninae, and weak support for the paraphyly of Brookesiinae (Figures 1, 15). The sampled species of the Brookesia nasus group appear as the sister group to all other chamaeleonids (the latter clade weakly supported) as found by some previous Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 authors [136], though other studies have recovered a monophyletic Brookesia [137,138]. Within Chamaeleoninae (Figure 15), we find strong support for the monophyly of most genera and species-level relationships. However, we find strong support for the non-monophyly of Calumma, with some species strongly placed with Chamaeleo, others strongly placed with Rieppeleon, and a third set weakly placed with Nadzikambia + Rhampoleon. While non-monophly of Calumma has also been found in previous studies [138], a recent study strongly supports monophyly of Brookesia and weakly supports monophyly of Calumma [139]. Monophyly of Agamidae is strongly supported (Figure 16; SHL = 100), contrary to some previous estimates [15,31]. Most relationships among agamid subfamilies and genera are strongly supported (Figure 16), and largely congruent with earlier studies [17,29,34,140]. There are some differences with earlier studies. For example, previous studies based on 29–44 loci [20,29,34] placed Hydrosaurinae as sister to Amphibolurinae + (Agaminae + Draconinae) with strong support, whereas we place Hydrosaurinae as the sister-group to Amphibolurinae with weak support. Other authors [140] placed Leiolepiedinae with Uromastycinae, but we (and most other studies) place Uromastycinae as the sister group to all other agamids. Our phylogeny indicates several taxonomic problems within amphibolurine agamids (Figure 16). The genera Moloch and Chelosania render Hypsilurus paraphyletic, although the support for the relevant clades is weak. The species Lophognathus gilberti is placed in a strongly supported clade with Chlamydosaurus and Amphibolurus, a clade that is not closely related to the other Lophognathus. Many of these taxonomic problems were also noted by previous authors [141]. Within agamine agamids (Figure 16), most relationships are well supported and monophyly of all sampled genera is strongly supported. In contrast, within draconine agamids (Figure 16), many intergeneric relationships are weakly supported, and some genera are non-monophyletic (Figure 16; see also [142]), including Gonocephalus (G. robinsonii is only distantly related to other Gonocephalus) and Japalura (with species distributed among three distantly related clades, including one allied with Ptyctolaemus, another with G. robinsonii, and a third with Pseudocalotes). Recent authors suggested dividing Laudakia into three genera (Stellagama, Paralaudakia, and Laudakia) based on a non-phylogenetic analysis of morphology [143]. Here, Laudakia (as previously defined) is strongly supported as monophyletic (Figure 16), and this change is not necessitated by the phylogeny. Similarly, based on genetic and morphological data, recent authors [144] suggested resurrecting the genus Saara for Page 36 of 53 the basal clade of Uromastyx (U. asmussi, U. hardwickii, and U. loricata). However, Uromastyx (as previously defined) is strongly supported as monophyletic in our results (Figure 16) and in those of the recent revision [144], and this change is not needed. We therefore retain Laudakia and Uromastyx as previously defined, to preserve taxonomic stability in these groups [113]. We note that recent studies have also begun to revise species limits in other groups such as Trapelus [145], and taxa such as T. pallidus (Figure 16) may represent populations within other species. Within Pleurodonta we generally confirm the monophyly and composition of the clades that were ranked as families (or subfamilies) within the group (e.g. Phrynosomatidae, Opluridae, Leiosauridae, Leiocephalidae, and Corytophanidae; Figures 1, 17, 18, 19) based on previous molecular studies [31,33,34] and earlier morphological analyses [146,147]. One important exception is the previously recognized Polychrotidae. Our results confirm that Anolis and Polychrus are not sister taxa (Figures 1, 18, 19), as also found in some previous molecular studies [31,33,34], but not others [20,29]. Our results provide strong support for non-monophyly of Polychrotidae, placing Polychrus with Hoplocercidae (SHL = 99) and Anolis with Corytophanidae (SHL = 99; the latter also found by [34]). Recent analyses placing Anolis with Polychrus showed only weak support for this relationship [20,29], despite many loci (30–44). We support continued recognition of Dactyloidae for Anolis and Polychrotidae for Polychrus [34], based on a limited number of loci but extensive taxon sampling. We note that these families are still monophlyetic, even if they prove to be sister taxa. Interestingly, our results for relationships among pleurodont families differ from most previous studies, and are surprisingly well-supported in some cases by SHL values (but see below). In previous studies, many relationships among pleurodont families were poorly supported by Bayesian posterior probabilities and by parsimony and likelihood bootstrap values, though typically sampling fewer taxa or characters [17,31,33,148-151]. Studies including 29 nuclear loci found strong concatenated Bayesian support for many relationships but weak support from ML bootstrap analyses for many of the same relationships [34]. The latter pattern (typically weak ML support) was also found in an analysis including those same 29 loci and mitochondrial data for >150 species [29]. We also find a mixture of strongly and weakly supported clades, but with many relationships that are incongruent with these previous studies. First, we find that Tropiduridae is weakly supported as the sister group to all other pleurodonts (also found by [29]), followed successively (Figures 1, 17, 18, 19) by Iguanidae, Leiocephalidae, Crotaphytidae + Phrynoso- Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 matidae, Polychrotidae + Hoplocercidae, and Corytophanidae + Dactyloidae. The relatively strong support for the clades Crotaphytidae + Phrynosomatidae (SHL = 87), Polychrotidae + Hoplocercidae (SHL = 99), and Corytophanidae + Dactyloidae (SHL = 99) is largely unprecedented in previous studies (although Corytophanidae + Dactyloidae is strongly supported in some Bayesian analyses [34]). As in many previous analyses, deeper relationships among the families remain weakly supported. We also find a strongly supported clade containing Liolaemidae, Opluridae, and Leiosauridae (SHL = 95), with Opluridae + Leiosauridae also strongly supported (SHL = 99). Both clades have also been found in previous studies [149,151], including studies based on 29 or more nuclear loci [20,29,34]. We note that previous studies have shown strong support for some pleurodont relationships (e.g. basal placement of phrynosomatids; see [34]), only to be strongly overturned with additional data [20,29]. Therefore, the relationships found here should be taken with some caution (even if strongly supported), with the possible exception of the recurring clade of Liolaemidae + (Opluridae + Leiosauridae). All pleurodont families are strongly supported as monophyletic (SHL > 85). Within the pleurodont families, our results generally support the current generic-level taxonomy (Figures 17, 18, 19). However, there are some exceptions. Within Tropiduridae (Figure 17), Tropidurus is paraphyletic with respect to Eurolophosaurus, Strobilurus, Uracentron, and Plica. Within Opluridae (Figure 18), the monotypic genus Chalarodon renders Oplurus paraphyletic. Two leiosaurid genera are also problematic (Figure 18). In Enyaliinae, Anisolepis is paraphyletic with respect to Urostrophus, and this clade is nested within Enyalius. In Leiosaurinae, Pristidactylus is rendered paraphyletic by Leiosaurus and Diplolaemus (Figure 18). Within Dactyloidae, a recent study re-introduced a more subdivided classification of anoles [152], an issue that has been debated extensively in the past [153-156]. Our results support the monophyly of all the genera recognized by recent authors [152], including Anolis, Audantia, Chamaelinorops, Dactyloa, Deiroptyx, Norops, and Xiphosurus (see Figure 19). However, since Anolis is monophyletic as traditionally defined, we retain that definition here (including the seven listed genera) for continuity with the recent literature [113,157]. Serpentes Relationships among the major serpent groups (Figure 1) are generally similar to other recent studies [20,35,36, 38,41,44,47,158-160]. We find that the blindsnakes, Scolecophidia (Figures 1, 20) are not monophyletic, as in previous studies [19,20,36,44,159,160]. Similar to some Page 37 of 53 previous studies [44,159], our data weakly place Anomalepididae as the sister taxon to all snakes, and the scolecophidian families Gerrhopilidae, Leptotyphlopidae, Typhlopidae, and Xenotyphlopidae as the sister-group to all other snakes excluding Anomalepididae (Figures 1, 20). Previous studies have also placed Anomalepididae as the sister-group to all non-scolecophidian snakes [19,20,35,36,158,160], in some cases with strong support [20]. Although it might appear that recent analyses of scolecophidian relationships [38] support monophyly of Scolecophidia (e.g. Figure 1 of [38]), the tree including non-snake outgroups from that study shows weak support for placing anomalepidids with alethinophidians, as in other studies [19,20,36,160]. We follow recent authors [38] in recognizing Xenotyphlopidae (strongly placed as the sister taxon of Typhlopidae) and Gerrhopilidae (strongly placed as the sister group of Xenotyphlopidae + Typhlopidae) as distinct families (Figure 20). Leptotyphlopidae is strongly supported as the sister group of a clade comprising Gerrhopilidae, Xenotyphlopidae, and Typhlopidae (Figure 20). As in previous studies [38,44], we find strong support for non-monophyly of several typhlopid genera (Afrotyphlops, Austrotyphlops, Ramphotyphlops, Letheobia, and Typhlops; Figure 20). There are also undescribed taxa (e.g. Typhlopidae sp. from Sri Lanka; [44]) of uncertain placement within this group (Figure 20). The systematics of typhlopoid snakes will thus require extensive revision in the future, with additional taxon and character sampling. Within Alethinophidia (SHL = 100), Aniliidae is strongly supported (SHL = 98) as the sister taxon of Tropidophiidae (together comprising Anilioidea), and all other alethinophidians form a strongly supported sister group to this clade (SHL = 97; Figures 1, 21). The enigmatic family Xenophidiidae is weakly placed as the sistergroup to all alethinophidians exclusive of Anilioidea (Figures 1, 21). The family Bolyeriidae is weakly placed as the sister-group to pythons, boas, and relatives (Booidea), which are strongly supported (SHL = 88). Relationships in this group are generally consistent with other recent molecular studies [20,35-37,47,159]. Relationships among other alethinophidians are a mixture of strongly and weakly supported nodes (Figures 1, 21). We find strong support (SHL = 100) for a clade containing Anomochilidae + Cylindrophiidae + Uropeltidae. This clade of three families is strongly supported (SHL = 89) as the sister taxon to Xenopeltidae + (Loxocemidae + Pythonidae). Together, these six families form a strongly supported clade (SHL = 89; Figures 1, 21) that is weakly supported as the sister group to the strongly supported clade of Boidae + Calabariidae. Within the clade of Anomochilidae, Cylindrophiidae, and Uropeltidae (Figure 21), we weakly place Anomochilus as the sister Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 group to Cylindrophiidae [44], in contrast to previous studies which placed Anomochilus within Cylindrophis [161]. However, support for monophyly of Cylindrophis excluding Anomochilus is weak (Figure 21). As in previous studies [44,162], we find several taxonomic problems within Uropeltidae (Figure 21). Specifically, Rhinophis and Uropeltis are paraphyletic with respect to each other and to Pseudotyphlops. The problematic taxa are primarily Sri Lankan [44], and forthcoming analyses will address these issues. Within Pythonidae (Figure 21), the genus Python is the sister group to all other genera. Some species that were traditionally referred to as Python (P. reticulatus and P. timoriensis) are instead sister to an Australasian clade consisting of Antaresia, Apodora, Aspidites, Bothrochilus, Leiopython, Liasis, and Morelia (Figure 21). These taxa (P. reticulatus and P. timoriensis) have been referred to as Broghammerus, a name originating from an act of "taxonomic vandalism" (i.e. an apparently intentional attempt to disrupt stable taxonomy) in a non-peer reviewed organ without data or analyses [163,164]. However, this name was, perhaps inadvertently, subsequently used by researchers in peer-reviewed work [165] and has entered into somewhat widespread usage [1]. This name should be ignored and replaced with a suitable substitute. Within the Australasian clade (Figure 21), Morelia is paraphyletic with respect to all other genera, and Liasis is non-monophyletic with respect to Apodora, although many of the relevant relationships are weakly supported. Within Boidae (Figure 21), our results and those of other recent studies [20,36,47,48,150,166] have converged on estimated relationships that are generally similar to each other but which differ from traditional taxonomy [167]. However, the classification has yet to be modified to reflect this, and we rectify this situation here. We find that Calabariidae is nested within Boidae [150], but this is poorly supported, and contrary to most previous studies [47,48]. While Calabaria has been classified as an erycine boid in the past, this placement is strongly rejected here and in other studies [47,48]. If the current placement of Calabaria is supported in the future, it would require recognition as the subfamily Calabariinae in Boidae. The Malagasy boine genera Acrantophis and Sanzinia are placed as the sister taxa to a weakly-supported clade containing Calabariidae and a strongly supported clade (SHL = 99) comprising the currently recognized subfamilies Erycinae, Ungaliophiinae, and other boines (Figure 21). Regardless of the position of Calabariidae, this placement of Malagasy boines renders Boinae paraphyletic. We therefore resurrect the subfamily Sanziniinae [168] for Acrantophis and Sanzinia. This subfamily could be recognized as a distinct family if Page 38 of 53 future studies also support placement of this clade as distinct from other Boidae + Calabariidae. The genera Lichanura and Charina are currently classified as erycines [1], but are strongly supported as the sister group to Ungaliophiinae, as in previous studies [20,36,47,166]. We expand Ungaliophiinae to include these two genera (Figure 21), rather than erect a new subfamily for these taxa. The subfamily Ungaliophiinae is placed as the sister group to a well-supported clade (SHL = 87) containing the rest of the traditionally recognized Erycinae and Boinae. We restrict Erycinae to the Old World genus Eryx. The genus Candoia (Boinae) from Oceania and New Guinea [1], is placed as the sister taxon to a moderately supported clade (SHL = 83) consisting of Erycinae (Eryx) and the remaining genera of Boinae (Boa, Corallus, Epicrates, and Eunectes). To solve the non-monophyly of Boinae with respect to Erycinae (due to Candoia), we place Candoia in a new subfamily (Candoiinae, subfam. nov.; see Appendix I). Boinae then comprises the four Neotropical genera that have traditionally been classified in this group (Boa, Corallus, Epicrates, and Eunectes). We acknowledge that non-monophyly of Boinae could be resolved in other ways (e.g. expanding it to include Erycinae). However, our taxonomy maintains the traditionally used subfamilies Boinae, Erycinae, and Ungaliophiinae, modifies them to reflect the phylogeny, and recognizes the phylogenetically distinct boine clades as separate subfamilies (Candoiinae, Sanziniinae). Within Boinae, Eunectes renders Epicrates paraphyletic, but this is not strongly supported (see also [48]). Our results for advanced snakes (Caenophidia) are generally similar to those of other recent studies [41,42,169], and will only be briefly described. However, in contrast to most recent studies [20,36,41,42,81,159,160], Acrochordidae is here strongly placed (SHL = 95) as the sister group to Xenodermatidae. This clade is then the sister group to the remaining Colubroidea, which form a strongly supported clade (SHL = 100; Figures 1, 22). This relationship has been found in some previous studies [169,170], and was hypothesized by early authors [171]. Further evidence will be required to resolve this conclusively. Analyses based on concatenation of 20–44 loci do not support this grouping [20,36], though preliminary species-tree analyses of >400 loci do (Pyron et al., in prep.). Relationships in Pareatidae are similar to recent studies [172], and the group is strongly placed as the sister taxon to colubroids excluding xenodermatids (SHL = 100; Figures 1 , 22), as in most recent analyses (e.g. [41,43,44]). The family Viperidae is the sister group to all colubroids excluding xenodermatids and pareatids (Figure 1), as in other recent studies. The family Viperidae is strongly supported (Figure 22), as is the subfamily Viperinae, and the sister-group relationship between Azemiopinae and Cro- Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 talinae (SHL = 100). Our results generally support the existing generic-level taxonomy within Viperinae (Figure 22). However, we recover a strongly supported clade within Viperinae consisting of Daboia russelii, D. palaestinae, Macrovipera mauritanica, and M. deserti (Figure 22), as in previous studies [173]. We corroborate previous suggestions that these taxa be included in Daboia [174], though this has not been widely adopted [1]. The other Macrovipera species (including the type species) remain in that genus (Figure 22). Within Crotalinae (Figure 22), a number of genera appear to be non-monophyletic. The species Trimeresurus gracilis is strongly supported as the sister taxon to Ovophis okinavensis and distantly related to other Trimeresurus, whereas the other Ovophis are strongly placed as the sister group to Protobothrops. A well-supported clade (SHL = 90) containing Atropoides picadoi, Cerrophidion, and Porthidium renders Atropoides paraphyletic (see also [175]). The species Bothrops pictus, considered incertae sedis in previous studies [176], is here strongly supported as the sister taxon to a clade containing Rhinocerophis, Bothropoides, Bothriopsis, and Bothrops (Figure 22). Most of these relationships are strongly supported. Viperidae is strongly placed (SHL = 95) as the sister taxon to a well-supported clade (SHL = 100) containing Colubridae, Elapidae, Homalopsidae, and Lamprophiidae (Figure 1). Monophyly of Homalopsidae is also strongly supported (Figure 23). Within Homalopsidae, nonmonophyly of the genus Enhydris is strongly supported (Figure 23), and it should likely be split into multiple genera. Homalopsidae is weakly supported (SHL = 58) as the sister group of Elapidae + Lamprophiidae (Figure 1). This same relationship was also weakly supported by previous analyses [41,44], but other studies have found strong support for placing Homalopsidae as the sister group of a strongly supported clade including Elapidae, Lamprophiidae, and Colubridae [20,36], including data from >400 loci (Pyron et al., in prep.). Support for the monophyly of Lamprophiidae is strong (but excluding Micrelaps; see below), and most of its subfamilies are well-supported [40,41,177,178] including Atractaspidinae, Aparallactinae, Lamprophiinae, Prosymninae (weakly placed as the sister-group to Oxyrhabdium), Pseudaspidinae, Psammophiinae, and Pseudoxyrhophiinae (Figure 23). In Lamprophiidae, most genera are monophyletic based on our sampling (Figure 23). However, within Aparallactinae, Xenocalamus is strongly placed within Amblyodipsas, and in Atractaspidinae, Homoroselaps is weakly placed in Atractaspis. In Lamprophiinae, Lamprophis is paraphyletic with respect to Lycodonomorphus but support for the relevant clades is weak. The enigmatic genera Buhoma from Africa and Psammodynastes from Asia were both previously considered Page 39 of 53 incertae sedis within Lamprophiidae [41]. Here they are weakly placed as sister taxa, and more importantly, they form a strongly supported clade with the African genus Pseudaspis (Pseudaspidinae; SHL = 95; Figure 23). Therefore, we expand Pseudaspidinae to include these two genera. The genus Micrelaps (putatively an aparallactine; [1]) is weakly placed as the sister taxon to Lamprophiidae + Elapidae. Along with Oxyrhabdium (see above) and Montaspis [40], this genus is treated as incertae sedis in our classification (Appendix I). If future studies strongly support these relationships, they may require a new family for Micrelaps and possibly a new subfamily for Oxyrhabdium, though placement of these taxa has been highly variable in previous studies [40,41,44,81]. Monophyly of Elapidae is strongly supported (Figure 24), and Calliophis melanurus is strongly supported as the sister group to all other elapids (see also [44]). Within Elapidae (Figure 24), relationships are generally concordant with previous taxonomy, with some exceptions. The genera Toxicocalamus, Simoselaps, and Echiopsis are all divided across multiple clades, with strong support for many of the relevant branches. A recent study [46] has provided a generic re-classification of the sea snakes (Hydrophis group) to resolve the extensive paraphyly of genera found in previous studies (e.g. [179,180]). Our results support this classification. Monophyly of Colubridae and most of its subfamilies (sensu [41,44]) are strongly supported (Figures 1, 25, 26, 27, 28). However, relationships among many of these subfamilies are weakly supported (Figure 1), as in most previous studies [41,43,45,181]. The subfamilies Calamariinae and Pseudoxenodontinae are strongly supported as sister taxa, and weakly placed as the sister-group to the rest of Colubridae (Figure 25). There is a weakly supported clade (Figure 1) comprising Natricinae + (Dipsadinae + Thermophis), but the clade uniting the New World Dipsadinae with the Asian genus Thermophis is strongly supported (SHL = 100; Figure 28). Here, we place Thermophis (recently in Pseudoxenodontinae [41]) in Dipsadinae (following [182]), making it the first and only Asian member of this otherwise exclusively New World subfamily. However, despite the strong support for its placement here, placement of this taxon has been variable in previous analyses [41,182,183], and we acknowledge that future analyses may support recognition of a distinct subfamily (Thermophiinae). The clade of Natricinae and Dipsadinae is weakly supported as the sister group (Figures 1, 25, 26, 27, 28) to a clade containing Sibynophiinae [181] + (Colubrinae + Grayiinae). The subfamily Colubrinae is weakly supported; we find that the colubrine genera Ahaetulla, Chrysopelea, and Dendrelaphis form a strongly supported clade that is weakly placed as the sister group to Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 the rest of Colubrinae, which form a strongly supported clade (Figure 25). This clade was also placed with Grayiinae or Sibynophiinae in many preliminary analyses, rendering Colubrinae paraphyletic. This group of three genera has been strongly supported in the past, and only weakly placed with Colubrinae [41,44]. It is possible that future analyses will reveal that the clade of Ahaetulla, Chrysopelea, and Dendrelaphis is placed elsewhere in Colubridae with strong support, and thus merit recognition as a distinct subfamily (Ahaetuliinae). A notable feature of this clade is the presence of gliding flight in most species of Chrysopelea, less-developed nonflight jumping with similar locomotor origins in Dendrelaphis, and homologous glide-related traits in Ahaetulla [184]. Numerous colubroid genera are not included in our tree and are not clearly placed in subfamilies based on previous morphological evidence. In our classification, these genera are also considered incertae sedis within Colubridae, including Blythia, Cyclocorus, Elapoidis, Gongylosoma, Helophis, Myersophis, Oreocalamus, Poecilopholis, Rhabdops, and Tetralepis, as in previous classifications [1]. Our phylogeny reveals numerous taxonomic problems within Colubrinae (Figures 25, 26). The genus Boiga is paraphyletic with respect to Crotaphopeltis, Dipsadoboa, Telescopus, Toxicodryas, and Dasypeltis, with strong support (Figure 25). The genus Philothamnus is paraphyletic with respect to Hapsidophrys (Figure 25). The genus Coluber is split between Old World and New World clades (Figures 25, 26). The species Hierophis spinalis is sister to Eirenis to the exclusion of the other Hierophis species (Figure 25). The genus Dryocalamus is nested within Lycodon (Figure 26). The species Chironius carinatus and C. quadricarinatus are weakly placed in a clade of Neotropical colubrines only distantly related to the other Chironius species (Figure 26). The genus Drymobius renders Dendrophidion paraphyletic (Figure 26). The monotypic genus Rhynchophis renders the two species of Rhadinophis paraphyletic (Figure 26). The genus Coronella is rendered paraphyletic (Figure 26) by Oocatochus with weak support (see also [185]). Finally, the genus Rhinechis is nested within Zamenis (Figure 26). We find numerous non-monophyletic genera within Natricinae (Figure 27), as in previous studies [41,44,78,186]. These non-monophyletic genera include the Asian genera Amphiesma, Atretium, and Xenocrophis. Among New World genera, we find Regina to be non-monophyletic with respect to most other genera, as in previous phylogenetic studies (e.g. [41,186]). Also, as in previous studies (e.g. [41,187]), we find that Adelophis [188] is nested deep within Thamnophis [189]. Finally, within a weakly supported Dipsadinae (Figure 28), we find non-monophyly of numerous genera, Page 40 of 53 as in many earlier studies (e.g. [41-43,190]). These problems of non-monophyly include Leptodeira (with respect to Imantodes), Geophis (with respect to Atractus), Atractus (with respect to Geophis), Sibynomorphus (with respect to Dipsas), Dipsas (with respect to Sibynomorphus), Taeniophallus (with respect to Echinanthera), and Echinanthera (with respect to Taeniophallus). Recent revisions have begun to tackle these problems [42,43,190], but additional taxon and character sampling will be crucial to resolve relationships and taxonomy. Discussion In this study, we provide a phylogenetic estimate for 4161 species of squamates based on molecular data from up to 12 genes per species, combining much of the relevant data used in previous molecular phylogenetic analyses. This tree provides a framework for future evolutionary studies, spanning from the species level to relationships among families, utilizing a common set of branch lengths. These estimated branch lengths are critically important for most phylogenetic comparative methods. To further facilitate use of this phylogeny in comparative studies, we provide the Newick version of this tree (with estimated branch lengths) in DataDryad repository 10.5061/dryad.82h0m and Additional file 1: Data File S1. Our results also suggest that the branch lengths in this tree should not generally be compromised by missing data for some genes in some taxa. Our results also reveal many problems in squamate classification at nearly all phylogenetic levels. We make several changes to higher-level taxonomy based on this phylogeny, including changes to the traditionally recognized subfamilies of boid snakes (i.e. resurrecting Sanziniinae for the boine genera Acrantophis and Sanzinia, erecting Candoiinae for the boine genus Candoia, and moving Lichanura and Charina from Erycinae to Ungaliophiinae), lamprophiid snakes (expansion of Pseudaspidinae to include the formerly incertae sedis genera Buhoma and Psammodynastes), colubrid snakes (expansion of Dipsadinae to include the Asian pseudoxenodontine genus Thermophis), and gymnophthalmid lizards (recognition of Bachiinae for the tribe Bachiini, containing Bachia) and scincid lizards (synonymizing Feylininae with Scincinae to yield a total of three scincid subfamilies: Acontiinae, Lygosominae, and Scincinae). In Appendix I, we list the generic content of all families and subfamilies. We also find dozens of problems at the genus level, many of which have been identified previously, and which we defer the resolution of to future studies. Our results also highlight potential problems in recent proposals to modify the classification of scincid [112] and teiid lizards [123]. In addition to synthesizing existing molecular data for squamate phylogeny, our analyses also reveal several Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 apparently novel findings (Figures 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28). Given space constraints, we cannot detail every deviation from previous phylogenetic hypotheses (especially pre-molecular studies). Nevertheless, we focus on three sets of examples. First, we find some relatively novel, strongly-supported relationships at the family level. These include the placement of Helodermatidae (as sister to Xenosauridae, Anguidae, and Anniellidae) and the placement of Xenodermatidae as the sister taxon to Acrochordidae (rendering Colubroidea paraphyletic), in contrast to most recent analyses of anguimorphs and snakes (see above). We also find some novel, strongly supported relationships among pleurodont families, but we acknowledge that these may be overturned in future studies. The second example is the higher-level relationships within Scincidae, the largest family of lizards [1]. No previous studies examining higher-level relationships within the group included more than ~50 species [50,51]. In this study, we sample 683 skink species (Figures 6, 7, 8, 9, 10), and our phylogeny provides a unique resolution of higher-level skink relationships. Some previous researchers [51] placed acontiines as the sister group to all other skinks, but suggested that scincines and lygosomines were paraphyletic with respect to each other (with feyliniines placed with scincines). In contrast, others [50] suggested that acontiines, feyliniines, and lygosomines were all nested inside scincines (but with each of those three subfamilies as monophyletic), although many clades were only weakly supported. Here (Figures 1, 6, 7, 8, 9, 10), we find that acontiines are the sister group to a strongly supported clade consisting of a monophyletic Scincinae and a monophyletic Lygosominae (excepting the weakly supported placement of Ateuchosaurus and placement of Feyliniinae in Scincinae). Third, our phylogeny reveals numerous genera that appear to be non-monophyletic, with many of these cases having strong support for the associated nodes. Our examples include genera in many families, including dibamids, diplodactylids, gekkonids, phyllodactylids, gerrhosaurids, scincids, teiids, gymnophthalmids, lacertids, anguids, chamaeleonids, agamids, tropidurids, oplurids, leiosaurids, typhlopids, pythonids, uropeltids, boids, viperids, lamprophiids, elapids, and colubrids (see Results). Although many problems noted here were found in previous studies, some seem to be new, such as placement of Crocodilurus and Draceana within Tupinambis (in Teiidae; Figure 11) and Coloptychon within Gerrhonotus (in Anguidae; Figure 14). Our study also offers an important test of higher-level squamate relationships using a very different sampling strategy than that used in most previous analyses. Squamates have traditionally been divided into two clades based Page 41 of 53 on morphology, Iguania and Scleroglossa (e.g. [13,21]). Despite considerable disagreement among morphologybased hypotheses, this basic division is supported by nearly all phylogenetic analyses based on morphological data [13-15,19,22,95,191]. In contrast, our results and those of most previous molecular analyses strongly support placement of iguanians with anguimorphs and snakes [16-20,23,24]. The causes of this conflict remain unclear, but may be related to morphological traits associated with different feeding strategies of iguanian and (traditional) scleroglossan squamates [3,17]. Additionally, analyses of morphology often place dibamids, amphisbaenians, snakes, and (in some cases) some scincids and anguids in a single clade [13-15]. Our analyses do not support such a clade (Figure 1), nor do other analyses of molecular data alone [17-20], or analyses of combined molecular and morphological data [19]. Instead, these morphological results seem to be explained by convergence associated with burrowing (e.g. [19]). Overall, molecular datasets have shown overwhelmingly strong support for placement of dibamids and gekkonids at the base of the tree, amphisbaenians with lacertoids, and iguanians with snakes and anguimorphs [17-20,23]. These results have now been corroborated with up to 22 genes (15794 bp) for 45 taxa [19], 25 genes (19020 bp) for 64 taxa [16], and 44 genes (33717 bp) for 161 taxa [20]. We now support this basic topology with 4161 species sampled for up to 12 genes each (up to 12896 bp). Nevertheless, despite the overall strong support for most of the tree (i.e. 70% of all nodes have SHL > 85), certain clades remain poorly supported (e.g. relationships among many pleurodont iguanian families; Figures 1, 17, 18, 19). A potential criticism of the supermatrix approach used here is that this weak support may occur due to missing data. However, previous studies of 8 datasets have shown explicitly that there is typically little relationship between branch support for terminal taxa and the amount of missing data [85]. Instead, these patterns of weak support are more likely to reflect short underlying branch lengths [20,36,41], and may be difficult to resolve even with more complete taxonomic and genomic sampling. Indeed, as noted above, many of the weakly supported nodes in our phylogeny are also weakly supported in analyses with little missing data (<20%) and large numbers of genes (e.g. 44 genes as in [20]), such as the relationships of many pleurodont lizard families and colubroid snake families and subfamilies. We acknowledge that the differences between our results and previous studies (noted above) do not necessarily mean that our results are right and those of previous studies are wrong. In some cases, we provide strong support for novel relationships when previous, conflicting studies showed only weak support (as in scincids, see above). In Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 other cases, our results disagree with other studies for clades that were strongly supported (e.g. placement of xenodermatids). In the best-case scenario, these conflicts may be resolved because our results are correct, possibly reflecting the beneficial effects of adding taxa and the associated subdivision of long branches [25,26,28,87, 192-194]. Furthermore, in many cases, we are including more genes than used in previous studies of particular clades, increasing sampling of characters and loci. This should generally reduce spurious results caused by sampling few characters and by incongruence between gene and species trees. However, other explanations for incongruence between our results and previous studies are also possible. Adding taxa can potentially lead to incorrect results in some cases (e.g. [195]), such as when a long terminal branch is added that further subdivides a short internal branch. In other cases, conflicts with our results might reflect the impact of our sampling fewer nuclear genes and a correspondingly increased influence of mitochondrial data. Mitochondrial genes have relatively fast evolutionary rates (potentially exacerbating the impacts of long branches), and their phylogenetic resolution for a particular node may also reflect introgression or incomplete lineage sorting rather than the species phylogeny (review in [196]). Many taxa in the matrix are represented only by mitochondrial data, and highly variable mitochondrial genes might also overcome the influence of less variable nuclear genes in combined analyses (although this scenario does not seem to be common [196]). Such cases might explain some strongly supported conflicts between our results and those based on multiple nuclear loci. Another possibility is that some cases may represent failure to find the optimal tree (although we assume that these cases will likely show only weak support). We acknowledge that there are many reasons why our results may differ from previous studies, and the ultimate test of these novel findings will be corroboration in future studies that include more taxa and characters. This analysis also corroborates several recent studies suggesting that the supermatrix approach is a powerful strategy for large-scale phylogenetic inference [41,72, 73,75,76,197]. For example, even though each species had 81% missing data on average, we found that most species were placed in the families and genera expected based on previous taxonomy, often with very strong support. Furthermore, we found that incompleteness of terminal taxa is not related to branch lengths (at least not terminal branch lengths), suggesting that missing data are not significantly biasing branch-length estimates (see also [84,86,87]). Also, the ML models we used have been shown to be robust to missing data in large, sparse supermatrices [84]. Page 42 of 53 Even though we did find some subfamilies and genera to be non-monophyletic, similar relationships were often found in previous studies based on data matrices with only limited missing data (e.g. non-monophyly of boid snake subfamilies [47], lacertid and scincid lizard genera [67,111], and scolecophidian, dipsadine, and natricine snake genera [38,43,186]). We suggest that further resolution of the squamate tree will be greatly facilitated if researchers deliberately sample mitochondrial genes and nuclear genes that include the set of genes used here and in recent phylogenomic studies (e.g. [20]), to increase overlap between genes and taxa, and decrease missing data. With over 5000 species remaining to be included and only 12 genes sampled, our study is far from the last word on squamate phylogeny. We note that new data can easily be added to this matrix, in terms of both new taxa and new genes. Increased sampling of other nuclear genes is likely to be advantageous as well. Next-generation sequencing strategies and phylogenomic methods should help resolve difficult nodes [16,20,36,198-200], as should application of species-tree methods [201,202]. Species-tree analyses of 44 nuclear loci support many of these same clades across squamates [20], and data from >400 nuclear loci reinforces many of the relationships found here among the colubroid snake subfamilies (Pyron et al., in prep.). In addition, it would be useful to incorporate fossil taxa in future studies [15,19,22,86], utilizing the large morphological datasets that are now available [14,15]. Despite these areas for future studies, the present tree provides a framework for researchers analyzing patterns of squamate evolution at both lower and higher taxonomic levels (e.g. [10,11,203,204]), and for building a more complete picture of squamate phylogeny. Conclusions In this study, we provide a phylogenetic estimate for 4161 squamate species, based on a supermatrix approach. Our results provide important confirmation for previous studies based on more limited taxon sampling, and reveal new relationships at the level of families, genera, and species. We also provide a phylogenetic framework for future comparative studies, with a large-scale tree including a common set of estimated branch lengths. Finally, we provide a revised classification for squamates based on this tree, including changes in the higher-level taxonomy of gymnophthalmid and scincid lizards and boid, colubrid, and lamprophiid snakes. Methods Initial classification Our initial squamate classification is based on the June 2009 version of the Reptile Database [1] (http://www. reptile-database.org/), accessed in September of 2009 Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 when this research was begun. Minor modifications to this scheme were made, primarily to update changes in colubroid snake taxonomy [41-44,205]. This initial taxonomic database consists of 8650 species (169 amphisbaenians, 5270 lizards, 3209 snakes, and 2 tuataras), against which the classification of species in the molecular sequence database was fixed. While modifications and updates (i.e. new species, revisions) have been made to squamate taxonomy subsequently, these are minor and should have no impact on our phylogenetic results. This database represents ~92% of the current estimated diversity of squamates (~9400 species as of December 2012). Throughout the paper, we refer to the updated version of squamate taxonomy from the December 2012 update of the Reptile Database [1], incorporating major, wellaccepted changes from recent studies (summarized in [1]). However, for large, taxonomic groups that have recently been broken up for reasons other than resolving paraphyly or matters of priority (e.g. in dactyloid and scincid lizards; see Results), we generally retain the older, more inclusive name in the interest of clarity, while providing references to the recent revision. We attempt to alter existing classifications as little as possible (see also [113]). Therefore, we generally only make changes when there is strong support for non-monophyly of currently recognized taxa and our proposed changes yield strongly supported monophyletic groups. Similarly, we only erect new taxa if they are strongly supported. Finally, although numerous genera are identified as being non-monophyletic in our tree, we refrain from changing genus-level taxonomy, given that our taxon sampling within many genera is limited. Molecular data Preliminary literature searches were conducted to identify candidate genes for which a substantial number of squamate species were sequenced and available on GenBank (with the sampled species spread across multiple families), and which were demonstrably useful in previous phylogenetic studies of squamates (see Introduction for references). Twelve genes were identified as meeting these criteria: seven nuclear genes (brain-derived neurotrophic factor [BDNF], oocyte maturation factor [c-mos], neurotrophin-3 [NT3], phosducin [PDC], G protein-coupled receptor 35 [R35], and recombinationactivating genes 1 [RAG-1] and 2 [RAG-2]); and five mitochondrial genes (12S/16S long and short subunit RNAs, cytochrome b [cyt-b], and nicotinamide adenine dehydrogenase subunits 2 [ND2] and 4 [ND4]). This sampling of genes does not include all available markers. For example, we omitted several nuclear and mitochondrial genes because they were available only for a limited subset of taxa. We also excluded tRNAs associated with Page 43 of 53 the protein-coding sequences, given their short lengths and difficulty in alignment across the large time scales considered here. To ensure maximal taxonomic coverage from the available data, searches were conducted on GenBank by family (stopping in October 2012), and the longest sequence for every species was gathered. Sequences totaling less than 250 bp for any species were not included. Only species in the taxonomic database were included in the sequence matrix, which resulted in the exclusion of numerous named taxa of ambiguous status, a few taxa described very recently, and many sequences labeled 'sp.' Some recently described phylogeographic lineages were also omitted. Species and GenBank accession numbers are available in Additional file 2: Table S1. With respect to the December 2012 update of the Reptile Database [1], we sampled 52 of 183 amphisbaenian species (28%) from 11 of 19 (58%) genera; 2847 of 5799 lizard species (49%) from 448 of 499 genera (90%); and 1262 of 3434 snake species (39%) in 396 of 500 genera (80%). This yielded a total of 4161 species in 855 genera in the final matrix, 44% of the 9416 known, extant squamate species in 84% of 1018 genera [1]. The species-level classification of squamates is in constant flux, and the numbers of species and genera changed even as this paper was under review. The extant species of tuatara (Sphenodon punctatus) was included as a nonsquamate outgroup taxon (see below). We acknowledge that our sampling of outgroup taxa is not extensive. However, placement of Sphenodon as the sister group to squamates is well-established by molecular analyses with extensive taxon sampling (e.g. [16,128,206]) and morphological data (e.g. [13]). Alignment for protein-coding sequences was relatively straightforward. We converted them to amino acids, and then used the translation alignment algorithm in the program Geneious v4.8.4 (GeneMatters Corp.), with the default cost matrix (Blosum62) and gap penalties (open=12, extension=3). Alignments were relatively unambiguous after being trimmed for quality and maximum coverage (i.e. ambiguous end regions were removed, and most sequences began and ended at the same point). For the ribosomal RNA sequences (12S and 16S sequences), alignment was more challenging. Preliminary global alignments using the algorithms MUSCLE [207] and CLUSTAL [208] under a variety of gap-cost parameters yielded low-quality results (i.e. alignments with large numbers of gaps and little overlap of potentially homologous characters). We subsequently employed a twostep strategy for these data. We first grouped sequences by higher taxa (i.e. Amphisbaenia, Anguimorpha, Gekkota, Iguania, Scincomorpha, and Serpentes, though these are not all monophyletic as previously defined), for Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 which alignments were relatively straightforward under the default MUSCLE parameters. These were then combined using the profile alignment feature of MUSCLE, and the global alignment was subsequently updated using the "refine alignment" option. Minor adjustments were then made by eye, and ambiguously aligned end-regions were trimmed for maximum coverage and quality. We did not include partitions for stems and loops for the ribosomal sequences, although this has been shown to improve model fit in previous squamate studies (e.g. [82]). Although it is possible to assign individual nucleotide positions to these partitions, this would have been challenging given the large number of sequences, and the potential for stems and loops to shift across the many species and large time scales involved. Each species was represented by a single terminal taxon in the matrix. In many cases, sequences from multiple individuals of the same species were combined, to allow us to combine data from different genes for the same species. We acknowledge the possibility that in some cases this approach may cause us to combine genes from different species in the same terminal taxon (e.g. due to changing taxonomy or incorrect identifications). Additionally, many sequences are not from vouchered specimens, and it is possible that misidentified species are present on GenBank and in our matrix. However, most of our data came from lower-level phylogenetic studies, in which the identification of species by previous authors should be highly accurate. In addition, any such mistakes should be among closely related species, and lead to minimal phylogenetic distortion, as the grossest errors are easily identified. Some species were removed after preliminary analyses, due either to obvious sequencing errors (e.g. high BLAST homology with unrelated families or nonsquamates, excessive ambiguities) or a lack of overlap in genes sampled with other members of the same genus (leading to seemingly artificial paraphyly). We also excluded species with identical sequences between taxa across all genes, arbitrarily choosing the first taxon in alphabetical order to remain in the matrix. Additionally, we also removed a few apparent "rogue taxa" [75,77]. These were identified by their poor support and suspect placement (e.g. in a clearly incorrect family), and were typically represented in the matrix by short fragments of single genes (e.g. an ND4 fragment from the enigmatic colubroid snake Oreocalamus hanitchsi). The final combined matrix contained sequence data for: 2335 species for 12S (including 56% of all 4162 taxa, 1395 bp), 2377 for 16S (57%, 1970 bp), 730 for BDNF (18%, 714 bp), 1671 for c-mos (40%, 903 bp), 1985 for cyt-b (48%, 1000 bp), 437 for NT3 (10%, 675 bp), 1860 for ND2 (45%, 960 bp), 1556 for ND4 (37%, 696 bp), 393 Page 44 of 53 for PDC (9%, 395 bp), 401 for R35 (10%, 768 bp), 1379 for RAG-1 (33%, 2700 bp), and 471 for RAG2 (11%, 720 bp). The total alignment consists of 12896 bp for 4162 taxa (4161 squamates and 1 outgroup). The mean length is 2497 bp of sequence data present per species from 3.75 genes (19% of the total matrix length of 12896 bp, or 81% missing data), and ranges from 270–11153 bp (2–86% complete). The matrix and phylogeny (see below) are available in DataDryad repository 10.5061/ dryad.82h0m. Clearly, many taxa had large amounts of missing data (some >95%), and on average each species had 81% missing cells. However, several lines of evidence suggest that these missing data are not generally problematic. First, a large body of empirical and theoretical studies has shown that highly incomplete taxa can be accurately placed in model-based phylogenetic analyses (and with high levels of branch support), especially if a large number of characters have been sampled (recent reviews in [84,85]). Second, several recent empirical studies have shown that the supermatrix approach (with extensive missing data in some taxa) yields generally wellsupported large-scale trees that are generally congruent with previous taxonomies and phylogenetic estimates (e.g. [41,48,72,73,75,76,197]). Third, recent studies have also shown that there is generally little relationship between the amount of missing data in individual taxa and the support for their placement on the tree [41,73,85]. Finally, we note that some highly incomplete taxa were unstable in their placement (“rogue taxa;" [75]), but these were removed prior to the analysis of the final matrix (see above). Our sampling design should be especially robust to the impacts of missing data for several reasons. Most importantly, most terminal taxon (species) had substantial data present (mean of 2497 bp per species) regardless of the number of missing data cells. Simulations (see reviews in [84,85]) suggest that the amount of data present is a key parameter in determining the accuracy with which incomplete taxa are placed in phylogenies, not the amount of data absent. Additionally, several genes (e.g. 12S/16S, cyt-b, and c-mos) were shared by many (>40%) of taxa. Thus, there was typically extensive overlap among the genes present for each taxon (as also indicated by the mean bp per species being much greater than the length of most genes). Limited overlap in gene sampling among taxa could be highly problematic, irrespective of the amount of missing data per se, but this does not appear to be a problem in our dataset. Finally, several nuclear genes (e.g. BDNF, c-mos, R35, and RAG-1) were congruently sampled in previous studies to represent most (>80%) squamate families and subfamilies (e.g. [20]), providing a scaffold of well-sampled taxa spanning all major clades, as recommended by recent authors [84]. Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Phylogenetic analyses We performed phylogenetic analyses of the 12-gene concatenated matrix using Maximum Likelihood (ML). We assessed node support using the non-parametric Shimodaira-Hasegawa-Like (SHL) implementation of the approximate likelihood-ratio test (aLRT; [94]). This involved a two-stage strategy. We first performed initial ML tree- inference using the program RAxML-Light v1.0.7 [209], a modification of the original RAxML algorithm [210]. This program uses the GTRCAT strategy for all genes and partitions, a high-speed approximation of the GTR+Γ model (general time-reversible with gamma-distribution of rate heterogeneity among sites). The GTR model is the only substitution model implemented in RAxML [210], and all other substitution models are simply special cases of the GTR model [211]. Previous analyses suggest that GTR is generally the best-fitting model for these genes and that they should be partitioned by gene and codon position [16,17,19,20,36,81]. To generate an initial ML estimate for final optimization and support estimation, we performed 11 ML searches from 11 parsimony starting trees generated under the default parsimony model in RAxMLv7.2.8. This number is likely to be sufficient when datasets contain many characters that have strong phylogenetic signal (A. Stamatakis, pers. comm.). Additionally, the dataset was analyzed with these settings (GTRCAT search from a randomized parsimony starting tree) numerous times (>20) as the final matrix was assembled and tested, representing hundreds of independent searches from random starting points. All of the estimated trees from these various analyses showed high overall congruence with the final topology. The concordance between the preliminary and final results suggests that the tree was not strongly impacted by searches stuck on local optima, and that it should be a good approximation of the ML tree. We then performed a final topology optimization and assessed support. We passed our best ML estimate of the phylogeny (based on GTRCAT) from RAxML-Light to RAxMLv7.2.8, which does an additional search (using the GTRGAMMA model) to produce a nearest-neighbor interchange (NNI)-optimized estimate of the ML tree. This optimization is needed to calculate the SHL version of the aLRT for estimating support values [94]. The SHLaLRT strategy approximates a test of the null hypothesis that the branch length subtending each node equals 0 (i.e. that the node can be resolved, rather than estimated as a polytomy) with a test of the more general null hypothesis that "the branch is incorrect" relative to the four next suboptimal arrangements of that node relative to the NNI-optimal arrangement [94]. Based on initial analyses, generating sufficient ML bootstrap replicates for a tree of this size proved computationally intractable, so we rely on SHL values alone to assess support. Page 45 of 53 The SHL approach has at least two major advantages over non-parametric bootstrapping for large ML trees: (i) values are apparently robust to many potential model violations and have the same properties as bootstrap proportions for all but the shortest branches [41,94,212], and (ii) values for short branches may be more accurate than bootstrap proportions, as support is evaluated based on whole-alignment likelihoods, rather than the frequency of re-sampled characters [94,213]. Additionally, the SHL approach is orders of magnitude faster than traditional bootstrapping [94,212,213], and it appears to be similarly robust to matrices with extensive missing data [41]. As in previous studies, we take a conservative view, considering SHL values of 85 or greater (i.e. a 15% chance that a branch is "incorrect") as strong support [41,212,213]. These analyses were performed on a 360-core SGI ICE supercomputing system ("ANDY") at the High Performance Computing Center at the City University of New York (CUNY). The final analysis was completed in 8.8 days of computer time using 188 nodes of the CUNY supercomputing cluster. Finally, we assessed the potential impact of missing data on our branch-length estimates. We performed linear regression (in R) of the proportional completeness of each terminal taxa (non-missing data in bp / maximum amount of non-missing data, 12896 bp) against the length of its terminal branch. This test addresses whether incomplete taxa have branch-length estimates that are consistently biased in one direction (shorter vs. longer) relative to more complete terminals. However, it does not directly test whether branch length estimates are correct or not, nor how branch length estimates are impacted by replacing non-missing data with missing data (see [87] for results suggesting that such replacements have little effect in real data sets). Appendix I Note that we only provide here an account for the one subfamily newly erected in this study. We do not provide accounts for subfamilies with changes in content (Boinae, Erycinae, Dipsadinae, Pseudaspidinae, Scincinae, Ungaliophiinae), that have been resurrrected (Sanziniinae), or that represent elevation of lower-ranked taxa (tribe Bachiini here recognized as Bachiinae). Candoiinae subfam. nov. (family Boidae) Type: genus and species Candoia carinata [214]. Content: one genus, 4 species; C. aspera, C. bibroni, C. carinata, C. paulsoni. Definition: this subfamily consists of the most recent common ancestor of the extant species of Candoia, and all its descendants. These species are morphologically distinguished in part from other boid snakes by a flattened Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 rostrum leading to an angular snout [215] and a wide premaxillary floor [167]. Distribution: these snakes are primarily restricted to the South Pacific islands of New Guinea and Melanesia, and the eastern Indonesian archipelago [150]. Remarks: the three species from this subfamily that are sampled in our tree are strongly supported as monophyletic (SHL = 100), and are well supported (SHL = 87) as the sister taxon to a moderately supported clade consisting of Erycinae + Boinae (SHL = 83). Page 46 of 53 Paroedura, Perochirus, Phelsuma, Pseudoceramodactylus, Pseudogekko, Ptenopus, Ptychozoon, Rhinogecko, Rhoptropella, Rhoptropus, Stenodactylus, Tropiocolotes, Urocotyledon, Uroplatus); Phyllodactylidae (Asaccus, Gymnodactylus, Haemodracon, Homonota, Phyllodactylus, Phyllopezus, Ptyodactylus, Tarentola, Thecadactylus); Pygopodidae (Aprasia, Delma, Lialis, Ophidiocephalus, Paradelma, Pletholax, Pygopus); Sphaerodactylidae (Aristelliger, Chatogekko, Coleodactylus, Euleptes, Gonatodes, Lepidoblepharis, Pristurus, Pseudogonatodes, Quedenfeldtia, Saurodactylus, Sphaerodactylus, Teratoscincus) Proposed Generic Composition of Higher Taxa Below, we list the familial and subfamilial assignment of all squamate genera from the December, 2012 update of the Reptile Database [1], updated to reflect some recent changes and the proposed subfamily level changes listed above. As this classification includes numerous taxa not sampled in our tree, we deal with them conservatively. For traditionally recognized families and subfamilies that we found to be monophyletic, we include all taxa traditionally assigned to them. Taxa are denoted incertae sedis if they are of ambiguous familial or subfamilial assignment due to uncertain placement in our tree, or due to absence from our tree and lack of assignment by previous authors. This classification includes 67 families and 56 subfamilies, and accounts for >9400 squamate species in 1018 genera [1]. Higher taxa are listed (more-or-less) phylogenetically (starting closest to the root; Figure 1), families are listed alphabetically within higher taxa, and subfamilies and genera are listed alphabetically within families. Squamata Dibamidae (Anelytropsis, Dibamus) Gekkota Carphodactylidae (Carphodactylus, Nephrurus, Orraya, Phyllurus, Saltuarius, Underwoodisaurus, Uvidicolus); Diplodactylidae (Amalosia, Bavayia, Correlophus, Crenadactylus, Dactylocnemis, Dierogekko, Diplodactylus, Eurydactylodes, Hesperoedura, Hoplodactylus, Lucasium, Mniarogekko, Mokopirirakau, Naultinus, Nebulifera, Oedodera, Oedura, Paniegekko, Pseudothecadactylus, Rhacodactylus, Rhynchoedura, Strophurus, Toropuku, Tukutuku, Woodworthia); Eublepharidae (Aeluroscalabotes, Coleonyx, Eublepharis, Goniurosaurus, Hemitheconyx, Holodactylus); Gekkonidae (Afroedura, Afrogecko, Agamura, Ailuronyx, Alsophylax, Asiocolotes, Blaesodactylus, Bunopus, Calodactylodes, Chondrodactylus, Christinus, Cnemaspis, Colopus, Crossobamon, Cryptactites, Cyrtodactylus, Cyrtopodion, Dixonius, Ebenavia, Elasmodactylus, Geckolepis, Gehyra, Gekko, Goggia, Hemidactylus, Hemiphyllodactylus, Heteronotia, Homopholis, Lepidodactylus, Luperosaurus, Lygodactylus, Matoatoa, Mediodactylus, Nactus, Narudasia, Pachydactylus, Paragehyra, Scincoidea Cordylidae, Cordylinae (Chamaesaura, Cordylus, Hemicordylus, Karusasaurus, Namazonurus, Ninurta, Ouroborus, Pseudocordylus, Smaug), Platysaurinae (Platysaurus); Gerrhosauridae, Gerrhosaurinae (Cordylosaurus, Gerrhosaurus, Tetradactylus), Zonosaurinae (Tracheloptychus, Zonosaurus); Scincidae, Acontiinae (Acontias, Typhlosaurus), Lygosominae (Ablepharus, Afroablepharus, Anomalopus, Asymblepharus, Ateuchosaurus, Bartleia, Bassiana, Bellatorias, Caledoniscincus, Calyptotis, Carlia, Cautula, Celatiscincus, Chioninia, Coeranoscincus, Coggeria, Cophoscincopus, Corucia, Cryptoblepharus, Ctenotus, Cyclodomorphus, Dasia, Egernia, Emoia, Eremiascincus, Eroticoscincus, Eugongylus, Eulamprus, Eumecia, Eutropis, Fojia, Geomyersia, Geoscincus, Glaphyromorphus, Gnypetoscincus, Graciliscincus, Haackgreerius, Hemiergis, Hemisphaeriodon, Insulasaurus, Isopachys, Kaestlea, Kanakysaurus, Lacertaspis, Lacertoides, Lamprolepis, Lampropholis, Lankascincus, Larutia, Leiolopisma, Lepidothyris, Leptoseps, Leptosiaphos, Lerista, Liburnascincus, Liopholis, Lioscincus, Lipinia, Lissolepis, Lobulia, Lygisaurus, Lygosoma, Mabuya, Marmorosphax, Menetia, Mochlus, Morethia, Nangura, Nannoscincus, Niveoscincus, Notoscincus, Oligosoma, Ophioscincus, Otosaurus, Panaspis, Papuascincus, Parvoscincus, Phoboscincus, Pinoyscincus, Prasinohaema, Proablepharus, Pseudemoia, Ristella, Saiphos, Saproscincus, Scincella, Sigaloseps, Simiscincus, Sphenomorphus, Tachygyia, Tiliqua, Trachylepis, Tribolonotus, Tropidophorus, Tropidoscincus, Tytthoscincus, Vietnascincus), Scincinae (Amphiglossus, Androngo, Barkudia, Brachymeles, Chabanaudia, Chalcides, Chalcidoseps, Eumeces, Eurylepis, Feylinia, Gongylomorphus, Hakaria, Janetaescincus, Jarujinia, Madascincus, Melanoseps, Mesoscincus, Nessia, Ophiomorus, Pamelaescincus, Paracontias, Plestiodon, Proscelotes, Pseudoacontias, Pygomeles, Scelotes, Scincopus, Scincus, Scolecoseps, Sepsina, Sepsophis, Sirenoscincus, Typhlacontias, Voeltzkowia); Xantusiidae, Cricosaurinae (Cricosaura), Lepidophyminae (Lepidophyma), Xantusiinae (Xantusia) Lacertoidea (including Amphisbaenia) Amphisbaenidae (Amphisbaena, Ancylocranium, Baikia, Chirindia, Cynisca, Dalophia, Geocalamus, Loveridgea, Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Mesobaena, Monopeltis, Zygaspis); Bipedidae (Bipes); Blanidae (Blanus); Cadeidae (Cadea); Gymnophthalmidae, Alopoglossinae (Alopoglossus, Ptychoglossus), Bachiinae (Bachia), Cercosaurinae (Anadia, Cercosaura, Echinosaura, Euspondylus, Macropholidus, Neusticurus, Opipeuter, Petracola, Pholidobolus, Placosoma, Potamites, Proctoporus, Riama, Riolama, Teuchocercus), Ecpleopinae (Adercosaurus, Amapasaurus, Anotosaura, Arthrosaura, Colobosauroides, Dryadosaura, Ecpleopus, Kaieteurosaurus, Leposoma, Marinussaurus, Pantepuisaurus), Gymnophthalminae (Acratosaura, Alexandresaurus, Calyptommatus, Caparaonia, Colobodactylus, Colobosaura, Gymnophthalmus, Heterodactylus, Iphisa, Micrablepharus, Nothobachia, Procellosaurinus, Psilophthalmus, Scriptosaura, Stenolepis, Tretioscincus, Vanzosaura), Rhachisaurinae (Rhachisaurus); Lacertidae, Gallotiinae (Gallotia, Psammodromus), Lacertinae (Acanthodactylus, Adolfus, Algyroides, Anatololacerta, Apathya, Archaeolacerta, Atlantolacerta, Australolacerta, Congolacerta, Dalmatolacerta, Darevskia, Dinarolacerta, Eremias, Gastropholis, Heliobolus, Hellenolacerta, Holaspis, Iberolacerta, Ichnotropis, Iranolacerta, Lacerta, Latastia, Meroles, Mesalina, Nucras, Omanosaura, Ophisops, Parvilacerta, Pedioplanis, Philochortus, Phoenicolacerta, Podarcis, Poromera, Pseuderemias, Scelarcis, Takydromus, Teira, Timon, Tropidosaura, Zootoca); Rhineuridae (Rhineura); Teiidae, Teiinae (Ameiva, Aspidoscelis, Cnemidophorus, Dicrodon, Kentropyx, Teius), Tupinambinae (Callopistes, Crocodilurus, Dracaena, Tupinambis); Trogonophiidae (Agamodon, Diplometopon, Pachycalamus, Trogonophis) Iguania Agamidae, Agaminae (Acanthocercus, Agama, Brachysaura, Bufoniceps, Laudakia, Phrynocephalus, Pseudotrapelus, Trapelus, Xenagama), Amphibolurinae (Amphibolurus, Chelosania, Chlamydosaurus, Cryptagama, Ctenophorus, Diporiphora, Hypsilurus, Intellagama, Lophognathus, Moloch, Physignathus, Pogona, Rankinia, Tympanocryptis), Draconinae (Acanthosaura, Aphaniotis, Bronchocela, Calotes, Ceratophora, Complicitus, Cophotis, Coryphophylax, Dendragama, Draco, Gonocephalus, Harpesaurus, Hypsicalotes, Japalura, Lophocalotes, Lyriocephalus, Mantheyus, Oriocalotes, Otocryptis, Phoxophrys, Psammophilus, Pseudocalotes, Pseudocophotis, Ptyctolaemus, Salea, Sitana, Thaumatorhynchus), Hydrosaurinae (Hydrosaurus), Leiolepidinae (Leiolepis), Uromastycinae (Uromastyx); Chamaeleonidae, Brookesiinae (Brookesia), Chamaeleoninae (Archaius, Bradypodion, Calumma, Chamaeleo, Furcifer, Kinyongia, Nadzikambia, Rhampholeon, Rieppeleon, Trioceros); Corytophanidae (Basiliscus, Corytophanes, Laemanctus); Crotaphytidae (Crotaphytus, Gambelia); Dactyloidae (Anolis); Hoplocercidae (Enyalioides, Hoplocercus, Morunasaurus); Iguanidae (Amblyrhynchus, Brachylophus, Conolophus, Ctenosaura, Cyclura, Dipsosaurus, Iguana, Sauromalus); Page 47 of 53 Leiocephalidae (Leiocephalus); Leiosauridae, Enyaliinae (Anisolepis, Enyalius, Urostrophus), Leiosaurinae (Diplolaemus, Leiosaurus, Pristidactylus); Liolaemidae (Ctenoblepharys, Liolaemus, Phymaturus); Opluridae (Chalarodon, Oplurus); Phrynosomatidae (Callisaurus, Cophosaurus, Holbrookia, Petrosaurus, Phrynosoma, Sceloporus, Uma, Urosaurus, Uta); Polychrotidae (Polychrus); Tropiduridae (Eurolophosaurus, Microlophus, Plica, Stenocercus, Strobilurus, Tropidurus, Uracentron, Uranoscodon) Anguimorpha Anguidae, Anguinae (Anguis, Dopasia, Ophisaurus, Pseudopus), Diploglossinae (Celestus, Diploglossus, Ophiodes), Gerrhonotinae (Abronia, Barisia, Coloptychon, Elgaria, Gerrhonotus, Mesaspis); Anniellidae (Anniella); Helodermatidae (Heloderma); Lanthanotidae (Lanthanotus); Shinisauridae (Shinisaurus); Varanidae (Varanus); Xenosauridae (Xenosaurus) Serpentes Acrochordidae (Acrochordus); Aniliidae (Anilius); Anomalepididae (Anomalepis, Helminthophis, Liotyphlops, Typhlophis); Anomochilidae (Anomochilus); Boidae, Boinae (Boa, Corallus, Epicrates, Eunectes), Candoiinae (Candoia), Erycinae (Eryx), Sanziniinae (Acrantophis, Sanzinia), Ungaliophiinae (Charina, Exiliboa, Lichanura, Ungaliophis); Bolyeriidae (Bolyeria, Casarea); Calabariidae (Calabaria); Colubridae incertae sedis (Blythia, Cyclocorus, Elapoidis, Gongylosoma, Helophis, Myersophis, Oreocalamus, Poecilopholis, Rhabdops, Tetralepis), Calamariinae (Calamaria, Calamorhabdium, Collorhabdium, Etheridgeum, Macrocalamus, Pseudorabdion, Rabdion), Colubrinae (Aeluroglena, Ahaetulla, Aprosdoketophis, Archelaphe, Argyrogena, Arizona, Bamanophis, Bogertophis, Boiga, Cemophora, Chilomeniscus, Chionactis, Chironius, Chrysopelea, Coelognathus, Coluber, Colubroelaps, Conopsis, Coronella, Crotaphopeltis, Cyclophiops, Dasypeltis, Dendrelaphis, Dendrophidion, Dipsadoboa, Dispholidus, Dolichophis, Drymarchon, Drymobius, Drymoluber, Dryocalamus, Dryophiops, Eirenis, Elachistodon, Elaphe, Euprepiophis, Ficimia, Geagras, Gonyophis, Gonyosoma, Gyalopion, Hapsidophrys, Hemerophis, Hemorrhois, Hierophis, Lampropeltis, Leptodrymus, Leptophis, Lepturophis, Limnophis, Liopeltis, Lycodon, Lytorhynchus, Macroprotodon, Mastigodryas, Meizodon, Oligodon, Oocatochus, Opheodrys, Oreocryptophis, Orthriophis, Oxybelis, Pantherophis, Philothamnus, Phyllorhynchus, Pituophis, Platyceps, Pseudelaphe, Pseudoficimia, Pseustes, Ptyas, Rhadinophis, Rhamnophis, Rhinechis, Rhinobothryum, Rhinocheilus, Rhynchocalamus, Rhynchophis, Salvadora, Scaphiophis, Scolecophis, Senticolis, Simophis, Sonora, Spalerosophis, Spilotes, Stegonotus, Stenorrhina, Symphimus, Sympholis, Tantilla, Tantillita, Telescopus, Thelotornis, Thrasops, Toxicodryas, Trimorphodon, Xenelaphis, Xyelodontophis, Zamenis), Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Dipsadinae (Adelphicos, Alsophis, Amastridium, Amnesteophis, Antillophis, Apostolepis, Arrhyton, Atractus, Boiruna, Borikenophis, Caaeteboia, Calamodontophis, Caraiba, Carphophis, Cercophis, Chapinophis, Chersodromus, Clelia, Coniophanes, Conophis, Contia, Coronelaps, Crisantophis, Cryophis, Cubophis, Darlingtonia, Diadophis, Diaphorolepis, Dipsas, Ditaxodon, Drepanoides, Echinanthera, Elapomorphus, Emmochliophis, Enuliophis, Enulius, Erythrolamprus, Farancia, Geophis, Gomesophis, Haitiophis, Helicops, Heterodon, Hydrodynastes, Hydromorphus, Hydrops, Hypsiglena, Hypsirhynchus, Ialtris, Imantodes, Leptodeira, Lioheterophis, Lygophis, Magliophis, Manolepis, Mussurana, Ninia, Nothopsis, Ocyophis, Omoadiphas, Oxyrhopus, Paraphimophis, Phalotris, Philodryas, Phimophis, Plesiodipsas, Pliocercus, Pseudalsophis, Pseudoboa, Pseudoeryx, Pseudoleptodeira, Pseudotomodon, Psomophis, Ptychophis, Rhachidelus, Rhadinaea, Rhadinella, Rhadinophanes, Rodriguesophis, Saphenophis, Schwartzophis, Sibon, Sibynomorphus, Siphlophis, Sordellina, Synophis, Tachymenis, Taeniophallus, Tantalophis, Thamnodynastes, Thermophis, Tomodon, Tretanorhinus, Trimetopon, Tropidodipsas, Tropidodryas, Uromacer, Uromacerina, Urotheca, Xenodon, Xenopholis), Grayiinae (Grayia), Natricinae (Adelophis, Afronatrix, Amphiesma, Amphiesmoides, Anoplohydrus, Aspidura, Atretium, Balanophis, Clonophis, Hologerrhum, Hydrablabes, Hydraethiops, Iguanognathus, Lycognathophis, Macropisthodon, Natriciteres, Natrix, Nerodia, Opisthotropis, Parahelicops, Pararhabdophis, Paratapinophis, Regina, Rhabdophis, Seminatrix, Sinonatrix, Storeria, Thamnophis, Trachischium, Tropidoclonion, Tropidonophis, Virginia, Xenochrophis), Pseudoxenodontinae (Plagiopholis, Pseudoxenodon), Sibynophiinae (Scaphiodontophis, Sibynophis); Cylindrophiidae (Cylindrophis); Elapidae (Acanthophis, Aipysurus, Aspidelaps, Aspidomorphus, Austrelaps, Bungarus, Cacophis, Calliophis, Cryptophis, Demansia, Dendroaspis, Denisonia, Drysdalia, Echiopsis, Elapognathus, Elapsoidea, Emydocephalus, Ephalophis, Furina, Hemachatus, Hemiaspis, Hemibungarus, Hoplocephalus, Hydrelaps, Hydrophis, Kolpophis, Laticauda, Loveridgelaps, Maticora, Micropechis, Micruroides, Micrurus, Naja, Notechis, Ogmodon, Ophiophagus, Oxyuranus, Parahydrophis, Parapistocalamus, Parasuta, Pseudechis, Pseudohaje, Pseudolaticauda, Pseudonaja, Rhinoplocephalus, Salomonelaps, Simoselaps, Sinomicrurus, Suta, Thalassophis, Toxicocalamus, Tropidechis, Vermicella, Walterinnesia); Gerrhopilidae (Gerrhopilus); Homalopsidae (Bitia, Brachyorrhos, Cantoria, Cerberus, Djokoiskandarus, Enhydris, Erpeton, Fordonia, Gerarda, Heurnia, Homalopsis, Myron, Pseudoferania); Lamprophiidae incertae sedis (Micrelaps, Montaspis, Oxyrhabdium), Aparallactinae (Amblyodipsas, Aparallactus, Brachyophis, Chilorhinophis, Elapotinus, Hypoptophis, Macrelaps, Polemon, Xenocalamus), Atractaspidinae (Atractaspis, Homoroselaps), Lamprophiinae (Boaedon, Bothrophthalmus, Chamaelycus, Page 48 of 53 Dendrolycus, Gonionotophis, Hormonotus, Inyoka, Lamprophis, Lycodonomorphus, Lycophidion, Pseudoboodon), Prosymninae (Prosymna), Psammophiinae (Dipsina, Hemirhagerrhis, Malpolon, Mimophis, Psammophis, Psammophylax, Rhagerhis, Rhamphiophis), Pseudaspidinae (Buhoma, Psammodynastes, Pseudaspis, Pythonodipsas), Pseudoxyrhophiine (Alluaudina, Amplorhinus, Bothrolycus, Brygophis, Compsophis, Ditypophis, Dromicodryas, Duberria, Exallodontophis, Heteroliodon, Ithycyphus, Langaha, Leioheterodon, Liophidium, Liopholidophis, Lycodryas, Madagascarophis, Micropisthodon, Pararhadinaea, Parastenophis, Phisalixella, Pseudoxyrhopus, Thamnosophis); Leptotyphlopidae (Epacrophis, Epictia, Leptotyphlops, Mitophis, Myriopholis, Namibiana, Rena, Rhinoleptus, Siagonodon, Tetracheilostoma, Tricheilostoma, Trilepida); Loxocemidae (Loxocemus); Pareatidae (Aplopeltura, Asthenodipsas, Pareas); Pythonidae (Antaresia, Apodora, Aspidites, Bothrochilus, Broghammerus, Leiopython, Liasis, Morelia, Python); Tropidophiidae (Trachyboa, Tropidophis); Typhlopidae (Acutotyphlops, Afrotyphlops, Austrotyphlops, Cyclotyphlops, Grypotyphlops, Letheobia, Megatyphlops, Ramphotyphlops, Rhinotyphlops, Typhlops); Uropeltidae (Brachyophidium, Melanophidium, Platyplectrurus, Plectrurus, Pseudotyphlops, Rhinophis, Teretrurus, Uropeltis); Viperidae, Azemiopinae (Azemiops), Crotalinae (Agkistrodon, Atropoides, Bothriechis, Bothriopsis, Bothrocophias, Bothropoides, Bothrops, Calloselasma, Cerrophidion, Crotalus, Deinagkistrodon, Garthius, Gloydius, Hypnale, Lachesis, Mixcoatlus, Ophryacus, Ovophis, Porthidium, Protobothrops, Rhinocerophis, Sistrurus, Trimeresurus, Tropidolaemus), Viperinae (Atheris, Bitis, Causus, Cerastes, Daboia, Echis, Eristicophis, Macrovipera, Montatheris, Montivipera, Proatheris, Pseudocerastes, Vipera); Xenodermatidae (Achalinus, Fimbrios, Stoliczkia, Xenodermus, Xylophis); Xenopeltidae (Xenopeltis); Xenophidiidae (Xenophidion); Xenotyphlopidae (Xenotyphlops) Additional files Additional file 1: Data File S1. The 4162-species ML phylogeny in Newick format; taxonomic changes are given in Additional file 2: Table S1. Additional file 2: Table S1. GenBank accession numbers for all taxa included in this analysis. Competing interests The authors declare that they have no competing interests. Authors' contributions RAP and JJW conceived the study. RAP, FTB, and JJW conducted analyses and checked results. RAP, FTB, and JJW wrote the MS. All authors read and approved the final manuscript. Acknowledgements We thank the many researchers who made this study possible through their detailed studies of squamate phylogeny with a (mostly) shared set of molecular markers, and uploading their sequence data to GenBank. We thank E. Paradis, J. Lombardo T. Guiher, R. Walsh, and P. Muzio for Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 computational assistance, T. Gamble, D. Frost, D. Cannatella, H. Zaher, F. Grazziotin, P. Uetz, T. Jackman, and A. Bauer for taxonomic advice, and A. Larson, M. Vences, and five anonymous reviewers for comments on this manuscript. The research was supported in part by the U.S. National Science Foundation, including a Bioinformatics Postdoctoral grant to R.A.P. (DBI-0905765), an AToL grant to J.J.W. (EF-0334923), and grants to the CUNY HPCC (CNS-0958379 and CNS-0855217). Author details 1 Department of Biological Sciences, The George Washington University, 2023 G St. NW, Washington, DC 20052, USA. 2Department of Biology, The Graduate School and University Center, The City University of New York, 365 5th Ave., New York, NY 10016, USA. 3Department of Biology, The College of Staten Island, The City University of New York, 2800 Victory Blvd., Staten Island, NY 10314, USA. 4Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721-0088, USA. Received: 30 January 2013 Accepted: 19 March 2013 Published: 29 April 2013 References 1. Uetz P: The Reptile Database. http://www.reptile-database.org/ Accessed December, 2012. 2. Greene HW: Snakes: the Evolution of Mystery in Nature. Berkeley: University of California Press; 1997. 3. Vitt LJ, Caldwell JP: Herpetology. 4th edition. Burlington: Elsevier; 2009. 4. Pianka ER, Vitt LJ: Lizards: Windows to the Evolution of Diversity. Berkeley: University of California Press; 2003. 5. Kasturiratne A, Wickremasinghe AR, de Silva N, Gunawardena NK, Pathmeswaran A, Premaratna R, Savioli L, Lalloo DG, de Silva HJ: The global burden of snakebite: a literature analysis and modelling based on regional estimates of envenoming and deaths. PLoS Med 2008, 5:1591–1604. 6. Mahdavi A, Ferreira L, Sundback C, Nichol JW, Chan EP, Carter DJD, Bettinger CJ, Patanavanich S, Chignozha L, Ben-Joseph E, et al: A biodegradable and biocompatible gecko-inspired tissue adhesive. Proc Natl Acad Sci USA 2008, 105:2307–2312. 7. Geim AK, Dubonos SV, Grigorieva IV, Novoselov KS, Zhukov AA, Shapoval SY: Microfabricated adhesive mimicking gecko foot-hair. Nat Mater 2003, 2:461–463. 8. Huey RB, Bennett AF: Phylogenetic studies of coadaptation: preferred temperatures versus optimal performance temperatures of lizards. Evolution 1987, 41:1098–1115. 9. Losos JB: The evolution of form and function: morphology and locomotor performance in West-Indian Anolis lizards. Evolution 1990, 44:1189–1203. 10. Wiens JJ, Brandley MC, Reeder TW: Why does a trait evolve multiple times within a clade? Repeated evolution of snakelike body form in squamate reptiles. Evolution 2006, 60:123–141. 11. Bergmann PJ, Irschick DJ: Vertebral evolution and the diversification of squamate reptiles. Evolution 2012, 66:1044–1058. 12. Losos JB, Hillis DM, Greene HW: Who speaks with a forked tongue? Science 2012, 338:1428–1429. 13. Estes R, de Queiroz K, Gauthier J: Phylogenetic relationships within Squamata. In Phylogenetic Relationships of the Lizard Families. Edited by Estes R, Pregill G. Stanford: Stanford University Press; 1988:119–281. 14. Gauthier JA, Kearney M, Maisano JA, Rieppel O, Behike ADB: Assembling the Squamate Tree of Life: perspectives from the phenotype and the fossil record. Bull Peabody Mus Nat Hist 2012, 53:3–308. 15. Conrad JL: Phylogeny and systematics of Squamata (Reptilia) based on morphology. Bull Am Mus Nat Hist 2008, 310:1–182. 16. Mulcahy DG, Noonan BP, Moss T, Townsend TM, Reeder TW, Sites JW Jr, Wiens JJ: Estimating divergence times and evaluating dating methods using phylogenomic and mitochondrial data in squamate reptiles. Mol Phylogenet Evol 2012, 65:974–991. 17. Townsend TM, Larson A, Louis E, Macey JR: Molecular phylogenetics of Squamata: the position of snakes, amphisbaenians, and dibamids, and the root of the squamate tree. Syst Biol 2004, 53:735–757. 18. Vidal N, Hedges SB: The phylogeny of squamate reptiles (lizards, snakes, and amphisbaenians) inferred from nine nuclear protein-coding genes. CR Biol 2005, 328:1000–1008. Page 49 of 53 19. Wiens JJ, Kuczynski CA, Townsend T, Reeder TW, Mulcahy DG, Sites JW: Combining phylogenomics and fossils in higher-level squamate reptile phylogeny: molecular data change the placement of fossil taxa. Syst Biol 2010, 59:674–688. 20. Wiens JJ, Hutter CR, Mulcahy DG, Noonan BP, Townsend TM, Sites JW, Reeder TW: Resolving the phylogeny of lizards and snakes (Squamata) with extensive sampling of genes and species. Biol Lett 2012, 8:1043–1046. 21. Camp CL: Classification of the lizards. Bull Am Mus Nat Hist 1923, 48:289–480. 22. Lee MSY: Convergent evolution and character correlation in burrowing reptiles: towards a resolution of squamate relationships. Biol J Linn Soc 1998, 65:369–453. 23. Vidal N, Hedges SB: Molecular evidence for a terrestrial origin of snakes. Proc R Soc B 2004, 271:S226–S229. 24. Fry BG, Vidal N, Norman JA, Vonk FJ, Scheib H, Ramjan SFR, Kuruppu S, Fung K, Hedges SB, Richardson MK, et al: Early evolution of the venom system in lizards and snakes. Nature 2006, 439:584–588. 25. Zwickl DJ, Hillis DM: Increased taxon sampling greatly reduces phylogenetic error. Syst Biol 2002, 51:588–598. 26. Poe S: Evaluation of the strategy of long-branch subdivision to improve the accuracy of phylogenetic methods. Syst Biol 2003, 52:423–428. 27. Heath TA, Zwickl DJ, Kim J, Hillis DM: Taxon sampling affects inferences of macroevolutionary processes from phylogenetic trees. Syst Biol 2008, 57:160–166. 28. Graybeal A: Is it better to add taxa or characters to a difficult phylogenetic problem? Syst Biol 1998, 47:9–17. 29. Blankers T, Townsend TM, Pepe K, Reeder TW, Wiens JJ: Contrasting global-scale evolutionary radiations: phylogeny, diversification, and morphological evolution in the major clades of iguanian lizards. Biol J Linn Soc 2013, 108:127–143. 30. Schulte JA, Moreno-Roark F: Live birth among iguanian lizards predates Pliocene-Pleistocene glaciations. Biol Lett 2010, 6:216–218. 31. Frost DR, Etheridge RE, Janies D, Titus TA: Total evidence, sequence alignment, evolution of polychrotid lizards, and a reclassification of the Iguania (Squamata: Iguania). Am Mus Novit 2001, 3343:38. 32. Macey JR, Schulte JA, Larson A, Ananjeva NB, Wang YZ, Pethiyagoda R, Rastegar-Pouyani N, Papenfuss TJ: Evaluating trans-Tethys migration: an example using acrodont lizard phylogenetics. Syst Biol 2000, 49:233–256. 33. Schulte JA, Valladares JP, Larson A: Phylogenetic relationships within Iguanidae inferred using molecular and morphological data and a phylogenetic taxonomy of iguanian lizards. Herpetologica 2003, 59:399–419. 34. Townsend TM, Mulcahy DG, Noonan BP, Sites JW, Kuczynski CA, Wiens JJ, Reeder TW: Phylogeny of iguanian lizards inferred from 29 nuclear loci, and a comparison of concatenated and species-tree approaches for an ancient, rapid radiation. Mol Phylogenet Evol 2011, 61:363–380. 35. Slowinski JB, Lawson R: Snake phylogeny: evidence from nuclear and mitochondrial genes. Mol Phylogenet Evol 2002, 24:194–202. 36. Wiens JJ, Kuczynski CA, Smith SA, Mulcahy DG, Sites JW, Townsend TM, Reeder TW: Branch lengths, support, and congruence: testing the phylogenomic approach with 20 nuclear loci in snakes. Syst Biol 2008, 57:420–431. 37. Lawson R, Slowinski JB, Burbrink FT: A molecular approach to discerning the phylogenetic placement of the enigmatic snake Xenophidion schaeferi among the Alethinophidia. J Zool 2004, 263:285–294. 38. Vidal N, Marin J, Morini M, Donnellan S, Branch WR, Thomas R, Vences M, Wynn A, Cruaud C, Hedges SB: Blindsnake evolutionary tree reveals long history on Gondwana. Biol Lett 2010, 6:558–561. 39. Adalsteinsson SA, Branch WR, Trape S, Vitt LJ, Hedges SB: Molecular phylogeny, classification, and biogeography of snakes of the family Leptotyphlopidae (Reptilia, Squamata). Zootaxa 2009, 2244:1–50. 40. Kelly CMR, Barker NP, Villet MH, Broadley DG: Phylogeny, biogeography and classification of the snake superfamily Elapoidea: a rapid radiation in the late Eocene. Cladistics 2009, 25:38–63. 41. Pyron RA, Burbrink FT, Colli GR, de Oca ANM, Vitt LJ, Kuczynski CA, Wiens JJ: The phylogeny of advanced snakes (Colubroidea), with discovery of a new subfamily and comparison of support methods for likelihood trees. Mol Phylogenet Evol 2011, 58:329–342. 42. Zaher H, Grazziotin FG, Cadle JE, Murphy RW, de Moura JC, Bonatto SL: Molecular phylogeny of advanced snakes (Serpentes, Caenophidia) with Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 43. 44. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. 61. 62. 63. 64. an emphasis on South American xenodontines: a revised classification and descriptions of new taxa. Pap Av Zool 2009, 49:115–153. Grazziotin FG, Zaher H, Murphy RW, Scrocchi G, Benavides MA, Zhang Y-P, Bonatto SL: Molecular phylogeny of the New World Dipsadidae (Serpentes: Colubroidea): a reappraisal. Cladistics 2012, 28:437–459. Pyron RA, Kandambi HKDK, Hendry CR, Pushpamal V, Burbrink FT, Somaweera R: Genus-level phylogeny of snakes reveals the origins of species richness in Sri Lanka. Mol Phylogenet Evol 2013, 66:969–978. Vidal N, Delmas AS, David P, Cruaud C, Coujoux A, Hedges SB: The phylogeny and classification of caenophidian snakes inferred from seven nuclear protein-coding genes. CR Biol 2007, 330:182–187. Sanders KL, Lee MSY, Bertozzi T, Rasmussen AR: Multilocus phylogeny and recent rapid radiation of the viviparous sea snakes (Elapidae: Hydrophiinae). Mol Phylogenet Evol 2012, 66:575–591. Noonan BP, Chippindale PT: Dispersal and vicariance: the complex evolutionary history of boid snakes. Mol Phylogenet Evol 2006, 40:347–358. Lynch VJ, Wagner GP: Did egg-laying boas break Dollo's law? Phylogenetic evidence for reversal to oviparity in sand boas (Eryx: Boidae). Evolution 2010, 64:207–216. Schmitz A, Brandley MC, Mausfeld P, Vences M, Glaw F, Nussbaum RA, Reeder TW: Opening the black box: phylogenetics and morphological evolution of the Malagasy fossorial lizards of the subfamily "Scincinae". Mol Phylogenet Evol 2005, 34:118–133. Brandley MC, Schmitz A, Reeder TW: Partitioned Bayesian analyses, partition choice, and the phylogenetic relationships of scincid lizards. Syst Biol 2005, 54:373–390. Whiting AS, Bauer AM, Sites JW: Phylogenetic relationships and limb loss in sub-Saharan African scincine lizards (Squamata: Scincidae). Mol Phylogenet Evol 2003, 29:582–598. Skinner A, Lee MSY, Hutchinson MN: Rapid and repeated limb loss in a clade of scincid lizards. BMC Evol Biol 2008, 8:310. Gamble T, Colli GR, Rodrigues MT, Werneck FP, Simons AM: Phylogeny and cryptic diversity in geckos (Phyllopezus; Phyllodactylidae; Gekkota) from South America's open biomes. Mol Phylogenet Evol 2012, 62:943–953. Gamble T, Daza JD, Colli GR, Vitt LJ, Bauer AM: A new genus of miniaturized and pug-nosed gecko from South America (Sphaerodactylidae: Gekkota). Zool J Linn Soc 2011, 163:1244–1266. Gamble T, Bauer AM, Colli GR, Greenbaum E, Jackman TR, Vitt LJ, Simons AM: Coming to America: multiple origins of New World geckos. J Evol Biol 2011, 24:231–244. Gamble T, Bauer AM, Greenbaum W, Jackman TR: Out of the blue: a novel, trans-Atlantic clade of geckos (Gekkota, Squamata). Zool Scripta 2008, 37:355–366. Oliver PM, Bauer AM, Greenbaum E, Jackman T, Hobbie T: Molecular phylogenetics of the arboreal Australian gecko genus Oedura Gray 1842 (Gekkota: Diplodactylidae): another plesiomorphic grade? Mol Phylogenet Evol 2012, 63:255–264. Nielsen SV, Bauer AM, Jackman TR, Hitchmough RA, Daugherty CH: New Zealand geckos (Diplodactylidae): cryptic diversity in a post-Gondwanan lineage with trans-Tasman affinities. Mol Phylogenet Evol 2011, 59:1–22. Gamble T, Greenbaum E, Jackman TR, Russell AP, Bauer AM: Repeated origin and loss of adhesive toepads in geckos. PLoS One 2012, 7:e39429. Wood PL Jr, Heinicke MP, Jackman TR, Bauer AM: Phylogeny of bent-toed geckos (Cyrtodactylus) reveals a west to east pattern of diversification. Mol Phylogenet Evol 2012, 65:992–1003. Giugliano LG, Collevatti RG, Colli GR: Molecular dating and phylogenetic relationships among Teiidae (Squamata) inferred by molecular and morphological data. Mol Phylogenet Evol 2007, 45:168–179. Reeder TW, Cole CJ, Dessauer HC: Phylogenetic relationships of whiptail lizards of the genus Cnemidophorus (Squamata: Teiidae): a test of monophyly, reevalution of karyotypic evolution, and review of hybrid origins. Am Mus Novit 2002, 3365:1–61. Pellegrino KCM, Rodrigues MT, Yonenaga-Yassuda Y, Sites JW: A molecular perspective on the evolution of microteiid lizards (Squamata, Gymnophthalmidae), and a new classification for the family. Biol J Linn Soc 2001, 74:315–338. Castoe TA, Doan TM, Parkinson CL: Data partitions and complex models in Bayesian analysis: the phylogeny of gymnophthalmid lizards. Syst Biol 2004, 53:448–469. Page 50 of 53 65. Pavlicev M, Mayer W: Fast radiation of the subfamily Lacertinae (Reptilia: Lacertidae): history or methodical artefact? Mol Phylogenet Evol 2009, 52:727–734. 66. Mayer W, Pavilcev M: The phylogeny of the family Lacertidae (Reptilia) based on nuclear DNA sequences: convergent adaptations to arid habitats within the subfamily Eremiainae. Mol Phylogenet Evol 2007, 44:1155–1163. 67. Fu JZ: Toward the phylogeny of the family Lacertidae: why 4708 base pairs of mtDNA sequences cannot draw the picture. Biol J Linn Soc 2000, 71:203–217. 68. Arnold EN, Arribas O, Carranza S: Systematics of the Palaearctic and Oriental lizard tribe Lacertini (Squamata: Lacertidae: Lacertinae), with descriptions of eight new genera. Zootaxa 2007, 1430:1–86. 69. Greenbaum E, Villanueva CO, Kusamba C, Aristote MM, Branch WR: A molecular phylogeny of equatorial African Lacertidae, with the description of a new genus and species from eastern Democratic Republic of the Congo. Zool J Linn Soc 2011, 163:913–942. 70. Mott T, Vieites DR: Molecular phylogenetics reveals extreme morphological homoplasy in Brazilian worm lizards challenging current taxonomy. Mol Phylogenet Evol 2009, 51:190–200. 71. Kearney M, Stuart BL: Repeated evolution of limblessness and digging heads in worm lizards revealed by DNA from old bones. Proc R Soc B 2004, 271:1677–1683. 72. Driskell AC, Ane C, Burleigh JG, McMahon MM, O'Meara BC, Sanderson MJ: Prospects for building the tree of life from large sequence databases. Science 2004, 306:1172–1174. 73. Wiens JJ, Fetzner JW, Parkinson CL, Reeder TW: Hylid frog phylogeny and sampling strategies for speciose clades. Syst Biol 2005, 54:719–748. 74. de Queiroz A, Gatesy J: The supermatrix approach to systematics. Trends Ecol Evol 2007, 22:34–41. 75. Thomson RC, Shaffer HB: Sparse supermatrices for phylogenetic inference: taxonomy, alignment, rogue taxa, and the phylogeny of living turtles. Syst Biol 2010, 59:42–58. 76. Pyron RA, Wiens JJ: A large-scale phylogeny of Amphibia including over 2,800 species, and a revised classification of extant frogs, salamanders, and caecilians. Mol Phylogenet Evol 2011, 61:543–583. 77. Hinchcliff CE, Roalson EH: Using supermatrices for phylogenetic inquiry: an example using the sedges. Syst Biol 2013, 62:205–219. 78. Guo P, Liu Q, Xu Y, Jiang K, Hou M, Ding L, Pyron RA, Burbrink FT: Out of Asia: natricine snakes support the Cenozoic Beringian Dispersal Hypothesis. Mol Phylogenet Evol 2012, 63:825–833. 79. Pyron RA, Burbrink FT: Neogene diversification and taxonomic stability in the snake tribe Lampropeltini (Serpentes: Colubridae). Mol Phylogenet Evol 2009, 52:524–529. 80. Burbrink FT, Lawson R: How and when did Old World ratsnakes disperse into the New World? Mol Phylogenet Evol 2007, 43:173–189. 81. Lawson R, Slowinski JB, Crother BI, Burbrink FT: Phylogeny of the Colubroidea (Serpentes): new evidence from mitochondrial and nuclear genes. Mol Phylogenet Evol 2005, 37:581–601. 82. Wiens JJ, Kuczynski CA, Arif S, Reeder TW: Phylogenetic relationships of phrynosomatid lizards based on nuclear and mitochondrial data, and a revised phylogeny for Sceloporus. Mol Phylogenet Evol 2010, 54:150–161. 83. Lemmon AR, Brown JM, Stanger-Hall K, Lemmon EM: The effect of ambiguous data on phylogenetic estimates obtained by maximum likelihood and Bayesian inference. Syst Biol 2009, 58:130–145. 84. Roure B, Baurain D, Philippe H: Impact of missing data on phylogenies inferred from empirical phylogenomic datasets. Mol Biol Evol 2013, 30:197–214. 85. Wiens JJ, Morrill MC: Missing data in phylogenetic analysis: reconciling results from simulations and empirical data. Syst Biol 2011, 60:719–731. 86. Pyron RA: Divergence time estimation using fossils as terminal taxa and the origins of Lissamphibia. Syst Biol 2011, 60:466–481. 87. Wiens JJ, Tiu J: Highly incomplete taxa can rescue phylogenetic analyses from the negative impacts of limited taxon sampling. PLoS One 2012, 7:e42925. 88. Scanlon JD, Lee MSY: The Pleistocene serpent Wonambi and the early evolution of snakes. Nature 2000, 403:416–420. 89. Tchernov E, Rieppel O, Zaher H, Polcyn MJ, Jacobs LL: A fossil snake with limbs. Science 2000, 287:2010–2012. 90. Rage J-C: Serpentes. Stuttgart: Gustav Fischer Verlag; 1984. 91. Estes R: Sauria terrestria, Amphisbaenia. Stuttgart: Gustav Fischer Verlag; 1983. Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 92. Holman JA: Fossil Snakes of North America: Origin, Evolution, Distribution, Paleoecology. Bloomington: Indiana University Press; 2000. 93. Rage J-C: Fossil history. In Snakes: Ecology and Evolutionary Biology. Edited by Seigel RA, Collins JT, Novak SS. New York: McMillan; 1987:51–76. 94. Anisimova M, Gascuel O: Approximate likelihood-ratio test for branches: a fast, accurate, and powerful alternative. Syst Biol 2006, 55:539–552. 95. Lee MSY: Squamate phylogeny, taxon sampling, and data congruence. Org Div Evol 2005, 5:25–45. 96. Townsend TM, Leavitt DH, Reeder TW: Intercontinental dispersal by a microendemic burrowing reptile (Dibamidae). Proc R Soc B 2011, 278:2568–2574. 97. Kluge AG: Cladistic relationships in the Gekkonoidea (Squamata, Sauria). Misc Pub Mus Zool Univ Mich 1987, 173:1–54. 98. Gamble T, Bauer AM, Greenbaum E, Jackman TR: Evidence for Gondwanan vicariance in an ancient clade of gecko lizards. J Biogeogr 2008, 35:88–104. 99. Melville J, Schulte JA, Larson A: A molecular study of phylogenetic relationships and evolution of antipredator strategies in Australian Diplodactylus geckos, subgenus Strophurus. Biol J Linn Soc 2004, 82:123–138. 100. Jennings WB, Pianka ER, Donnellan S: Systematics of the lizard family Pygopodidae with implications for the diversification of Australian temperate biotas. Syst Biol 2003, 52:757–780. 101. Bauer AM, Jackman TR, Sadlier RA, Whitaker AH: Revision of the giant geckos of New Caledonia (Reptilia: Diplodactylidae: Rhacodactylus). Zootaxa 2012, 3404:1–52. 102. Brown RM, Siler CD, Das I, Min Y: Testing the phylogenetic affinities of Southeast Asia's rarest geckos: flap-legged geckos (Luperosaurus), flying geckos (Ptychozoon) and their relationship to the pan-Asian genus Gekko. Mol Phylogenet Evol 2012, 63:915–921. 103. Vicario S, Caccone A, Gauthier J: Xantusiid "night" lizards: a puzzling phylogenetic problem revisited using likelihood-based Bayesian methods on mtDNA sequences. Mol Phylogenet Evol 2003, 26:243–261. 104. Hedges SB, Bezy RL, Maxson LR: Phylogenetic relationships and biogeography of xantusiid lizards, inferred from mitochondrial DNA sequences. Mol Biol Evol 1991, 8:767–780. 105. Smith HM: The name of the non-nominotypical subfamily of the lizard family Xantusiidae. Syst Zool 1987, 36:326–328. 106. Savage JM: The Amphibians and Reptiles of Costa Rica: a Herpetofauna between Two Continents, between Two Seas. Chicago: University of Chicago Press; 2002. 107. Crother BI, Miyamoto MM, Presch WF: Phylogeny and biogeography of the lizard family Xantusiidae. Syst Zool 1986, 35:37–45. 108. Stanley EL, Bauer AM, Jackman TR, Branch WR, Mouton PLFN: Between a rock and a hard polytomy: rapid radiation in the rupicolous girdled lizards (Squamata: Cordylidae). Mol Phylogenet Evol 2011, 58:53–70. 109. Frost DR, Janies D, Mouton PIN, Titus TA: A molecular perspective on the phylogeny of the girdled lizards (Cordylidae, Squamata). Am Mus Novit 2001, 3310:1–10. 110. Greer AE: A subfamilial classification of scincid lizards. Bull Mus Comp Zool 1970, 139:151–183. 111. Smith SA, Sadlier RA, Bauer AM, Austin CC, Jackman T: Molecular phylogeny of the scincid lizards of New Caledonia and adjacent areas: evidence for a single origin of the endemic skinks of Tasmantis. Mol Phylogenet Evol 2007, 43:1151–1166. 112. Hedges SB, Conn CE: A new skink fauna from Caribbean islands (Squamata, Mabuyidae, Mabuyinae). Zootaxa 2012, 3288:1–244. 113. Vences M, Guayasamin JM, Miralles A, de La Riva I: To name or not to name: criteria to promote economy of change in supraspecific Linnaean classification schemes. Zootaxa 2013, 3636:201–244. 114. Bauer AM: On the identity of Lacerta punctata Linnaeus, 1758, the type species of the genus Euprepis Wagler, 1830, and the generic assignment of Afro-Malagasy skinks. Afr J Herpetol 2003, 52:1–7. 115. Austin JJ, Arnold EN: Using ancient and recent DNA to explore relationships of extinct and endangered Leiolopisma skinks (Reptilia: Scincidae) in the Mascarene islands. Mol Phylogenet Evol 2006, 39:503–511. 116. Skinner A: Phylogenetic relationships and rate of early diversification of Australian Sphenomorphus group scincids (Scincoidea, Squamata). Biol J Linn Soc 2007, 92:347–366. 117. Linkem CW, Diesmos AC, Brown RM: Molecular systematics of the Philippine forest skinks (Squamata: Scincidae: Sphenomorphus): testing morphological hypotheses of interspecific relationships. Zool J Linn Soc 2011, 163:1217–1243. Page 51 of 53 118. Siler CD, Diesmos AC, Alcala AC, Brown RM: Phylogeny of Philippine slender skinks (Scincidae: Brachymeles) reveals underestimated species diversity, complex biogeographical relationships, and cryptic patterns of lineage diversification. Mol Phylogenet Evol 2011, 59:53–65. 119. Brandley MC, Ota H, Hikida T, de Oca ANM, Feria-Ortiz M, Guo XG, Wang YZ: The phylogenetic systematics of blue-tailed skinks (Plestiodon) and the family Scincidae. Zool J Linn Soc 2012, 165:163–189. 120. Crottini A, Dordel J, Kohler J, Glaw F, Schmitz A, Vences M: A multilocus phylogeny of Malagasy scincid lizards elucidates the relationships of the fossorial genera Androngo and Cryptoscincus. Mol Phylogenet Evol 2009, 53:345–350. 121. Sindaco R, Metallinou M, Pupin F, Fasola M, Carranza S: Forgotten in the ocean: systematics, biogeography and evolution of the Trachylepis skinks of the Socotra Archipelago. Zool Scripta 2012, 41:346–362. 122. Miralles A, Fuenmayor GR, Bonillo C, Schargel WE, Barros T, Garcia-Perez JE, Barrio-Amoros CL: Molecular systematics of Caribbean skinks of the genus Mabuya (Reptilia, Scincidae), with descriptions of two new species from Venezuela. Zool J Linn Soc 2009, 156:598–616. 123. Harvey MB, Ugueto GN, Gutberlet RL: Review of teiid morphology with a revised taxonomy and phylogeny of the Teiidae (Lepidosauria: Squamata). Zootaxa 2012, 3459:1–156. 124. Doan TM, Castoe TA: Phylogenetic taxonomy of the Cercosaurini (Squamata: Gymnophthalmidae), with new genera for species of Neusticurus and Proctoporus. Zool J Linn Soc 2005, 143:405–416. 125. Vidal N, Azvolinsky A, Cruaud C, Hedges SB: Origin of tropical American burrowing reptiles by transatlantic rafting. Biol Lett 2008, 4:115–118. 126. Vidal N, Hedges SB: The molecular evolutionary tree of lizards, snakes, and amphisbaenians. CR Biol 2009, 332:129–139. 127. Lee MSY: Hidden support from unpromising data sets strongly unites snakes with anguimorph 'lizards'. J Evol Biol 2009, 22:1308–1316. 128. Hugall AF, Foster R, Lee MSY: Calibration choice, rate smoothing, and the pattern of tetrapod diversification according to the long nuclear gene RAG-1. Syst Biol 2007, 56:543–563. 129. Macey JR, Schulte JA, Larson A, Tuniyev BS, Orlov N, Papenfuss TJ: Molecular phylogenetics, tRNA evolution, and historical biogeography in anguid lizards and related taxonomic families. Mol Phylogenet Evol 1999, 12:250–272. 130. Conrad JL, Ast JC, Montanari S, Norell MA: A combined evidence phylogenetic analysis of Anguimorpha (Reptilia: Squamata). Cladistics 2011, 27:230–277. 131. Collar DC, Schulte JA, Losos JB: Evolution of extreme body size disparity in monitor lizards (Varanus). Evolution 2011, 65:2664–2680. 132. Chippindale PT, Ammerman LK, Campbell JA: Molecular approaches to phylogeny of Abronia (Anguidae: Gerrhonotinae), with emphasis on relationships in subgenus Auriculabronia. Copeia 1998, 4:883–892. 133. Conroy CJ, Bryson RW, Lazcano D, Knight A: Phylogenetic placement of the pygmy alligator lizard based on mitochondrial DNA. J Herp 2005, 39:142–147. 134. Okajima Y, Kumazawa Y: Mitochondrial genomes of acrodont lizards: timing of gene rearrangements and phylogenetic and biogeographic implications. BMC Evol Biol 2010, 10:141. 135. Castoe TA, de Koning APJ, Kim HM, Gu WJ, Noonan BP, Naylor G, Jiang ZJ, Parkinson CL, Pollock DD: Evidence for an ancient adaptive episode of convergent molecular evolution. Proc Natl Acad Sci USA 2009, 106:8986–8991. 136. Raxworthy CJ, Forstner MRJ, Nussbaum RA: Chameleon radiation by oceanic dispersal. Nature 2002, 415:784–787. 137. Townsend TM, Vieites DR, Glaw F, Vences M: Testing species-level diversification hypotheses in Madagascar: the case of microendemic Brookesia leaf chameleons. Syst Biol 2009, 58:641–656. 138. Townsend TM, Tolley KA, Glaw F, Bohme W, Vences M: Eastward from Africa: palaeocurrent-mediated chameleon dispersal to the Seychelles islands. Biol Lett 2011, 7:225–228. 139. Tolley KA, Townsend TM, Vences M: Large-scale phylogeny of chameleons suggests African origins and Eocene diversification. Proc R Soc B 2013, 280:20130184. 140. Honda M, Ota H, Kobayashi M, Nabhitabhata J, Yong H-S, Sengoku S, Hikida T: Phylogenetic relationships of the family Agamidae (Reptilia: Iguania) inferred from mitochondrial DNA sequences. Zool Sci 2000, 17:527–537. 141. Hugall AF, Foster R, Hutchinson M, Lee MSY: Phylogeny of Australasian agamid lizards based on nuclear and mitochondrial genes: implications for morphological evolution and biogeography. Biol J Linn Soc 2008, 93:343–358. Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 142. Honda M, Ota H, Sengoku S, Yong HS, Hikida T: Molecular evaluation of phylogenetic significances in the highly divergent karyotypes of the genus Gonocephalus (Reptilia: Agamidae) from tropical Asia. Zool Sci 2002, 19:129–133. 143. Baig KJ, Wagner P, Ananjeva NB, Bohme W: A morphology-based taxonomic revision of Laudakia Gray, 1845 (Squamata: Agamidae). Vertebr Zool 2012, 62:213–260. 144. Wilms TM, Bohme W, Wagner P, Lutzmann N, Schmitz A: On the phylogeny and taxonomy of the genus Uromastyx Merrem, 1820 (Reptilia: Squamata: Agamidae: Uromastycinae): resurrection of the genus Saara Gray, 1845. Bonner zoologische Beiträge 2009, 56:55–99. 145. Wagner P, Melville J, Wilms TM, Schmitz A: Opening a box of cryptic taxa: the first review of the North African desert lizards in the Trapelus mutabilis Merrem, 1820 complex (Squamata: Agamidae) with descriptions of new taxa. Zool J Linn Soc 2011, 163:884–912. 146. Etheridge R, de Queiroz K: A phylogeny of Iguanidae. In Phylogenetic Relationships of the Lizard Families: Essays Commemorating Charles L Camp. Edited by Estes RD, Pregill GK. Stanford: Stanford University Press; 1988:283–367. 147. Frost DR, Etheridge R: A phylogenetic analysis and taxonomy of iguanian lizards (Reptilia: Squamata). Misc Publ Univ Kansas 1989, 81:1–65. 148. Macey JR, Larson A, Ananjeva NB, Papenfuss TJ: Evolutionary shifts in three major structural features of the mitochondrial genome among iguanian lizards. J Mol Evol 1997, 44:660–674. 149. Noonan BP, Chippindale PT: Vicariant origin of Malagasy reptiles supports late Cretaceous antarctic land bridge. Am Nat 2006, 168:730–741. 150. Noonan BP, Sites JW: Tracing the origins of iguanid lizards and boine snakes of the Pacific. Am Nat 2010, 175:61–72. 151. Schulte JA, Cartwright EM: Phylogenetic relationships among iguanian lizards using alternative partitioning methods and TSHZ1: a new phylogenetic marker for reptiles. Mol Phylogenet Evol 2009, 50:391–396. 152. Nicholson KE, Crother BI, Guyer C, Savage JM: It is time for a new classification of anoles (Squamata: Dactyloidae). Zootaxa 2012, 3477:1–108. 153. Poe S: Phylogeny of anoles. Herp Monogr 2004, 18:37–89. 154. Guyer C, Savage JM: Cladistic relationships among anoles (Sauria, Iguanidae). Syst Zool 1986, 35:509–531. 155. Losos JB: Lizards in an Evolutionary Tree: the Ecology of Adaptive Radiation in Anoles. Berkeley: University of California Press; 2009. 156. Cannatella DC, de Queiroz K: Phylogenetic systematics of the anoles: is a new taxonomy warranted? Syst Zool 1989, 38:57–69. 157. Poe S: 1986 redux: new genera of anoles (Squamata: Dactyloidae) are unwarranted. Zootaxa 2013, 3626:295–299. 158. Heise PJ, Maxson LR, Dowling HG, Hedges SB: Higher-level snake phylogeny inferred from mitochondrial DNA sequences of 12S rRNA and 16S rRNA genes. Mol Biol Evol 1995, 12:259–265. 159. Burbrink FT, Pyron RA: The taming of the skew: estimating proper confidence intervals for divergence dates. Syst Biol 2008, 57:317–328. 160. Pyron RA, Burbrink FT: Extinction, ecological opportunity, and the origins of global snake diversity. Evolution 2012, 66:163–178. 161. Gower DJ, Vidal N, Spinks JN, McCarthy CJ: The phylogenetic position of Anomochilidae (Reptilia: Serpentes): first evidence from DNA sequences. J Zool Syst Evol Res 2005, 43:315–320. 162. Cadle JE, Dessauer HC, Gans C, Gartside DF: Phylogenetic relationships and molecular evolution in uropeltid snakes (Serpentes, Uropeltidae): allozymes and albumin immunology. Biol J Linn Soc 1990, 40:293–320. 163. Wallach V, Wuster W, Broadley DG: In praise of subgenera: taxonomic status of cobras of the genus Naja Laurenti (Serpentes: Elapidae). Zootaxa 2009, 2236:26–36. 164. Williams D, Wuster W, Fry BG: The good, the bad and the ugly: Australian snake taxonomists and a history of the taxonomy of Australia's venomous snakes. Toxicon 2006, 48:919–930. 165. Rawlings LH, Rabosky DL, Donnellan SC, Hutchinson MN: Python phylogenetics: inference from morphology and mitochondrial DNA. Biol J Linn Soc 2008, 93:603–619. 166. Burbrink FT: Inferring the phylogenetic position of Boa constrictor among the Boinae. Mol Phylogenet Evol 2005, 34:167–180. 167. Kluge AG: Boine snake phylogeny and research cycles. Misc Publ Mus Zool Univ Mich 1991, 178:1–58. 168. Romer AS: Osteology of the Reptiles. Chicago: University of Chicago Press; 1956. 169. Kelly CMR, Barker NP, Villet MH: Phylogenetics of advanced snakes (Caenophidia) based on four mitochondrial genes. Syst Biol 2003, 52:439–459. Page 52 of 53 170. Kraus F, Brown WM: Phylogenetic relationships of colubroid snakes based on mitochondrial DNA sequences. Zool J Linn Soc 1998, 122:455–487. 171. Boulenger GA: Catalogue of snakes in the British Museum. London: British Museum of Natural History; 1894. 172. Guo P, Wu Y, He S, Shi H, Zhao E: Systematics and molecular phylogenetics of Asian snail-eating snakes (Pareatidae). Zootaxa 2011, 3001:57–64. 173. Garrigues T, Dauga C, Ferquel E, Choumet V, Failloux AB: Molecular phylogeny of Vipera Laurenti, 1768 and the related genera Macrovipera (Reuss, 1927) and Daboia (Gray, 1842), with comments about neurotoxic Vipera aspis aspis populations. Mol Phylogenet Evol 2005, 35:35–47. 174. Lenk P, Kalyabina S, Wink M, Joger U: Evolutionary relationships among the true vipers (Reptilia: Viperidae) inferred from mitochondrial DNA sequences. Mol Phylogenet Evol 2001, 19:94–104. 175. Castoe TA, Parkinson CL: Bayesian mixed models and the phylogeny of pitvipers (Viperidae: Serpentes). Mol Phylogenet Evol 2006, 39:91–110. 176. Fenwick AM, Gutberlet RL, Evans JA, Parkinson CL: Morphological and molecular evidence for phylogeny and classification of South American pitvipers, genera Bothrops, Bothriopsis, and Bothrocophias (Serpentes: Viperidae). Zool J Linn Soc 2009, 156:617–640. 177. Kelly CMR, Branch WR, Broadley DG, Barker NP, Villet MH: Molecular systematics of the African snake family Lamprophiidae Fitzinger, 1843 (Serpentes: Elapoidea), with particular focus on the genera Lamprophis Fitzinger 1843 and Mehelya Csiki 1903. Mol Phylogenet Evol 2011, 58:415–426. 178. Vidal N, Branch WR, Pauwels OSG, Hedges SB, Broadley DG, Wink M, Cruaud C, Joger U, Nagy ZT: Dissecting the major African snake radiation: a molecular phylogeny of the Lamprophiidae Fitzinger (Serpentes, Caenophidia). Zootaxa 2008, 1945:51–66. 179. Sanders KL, Lee MSY, Leys R, Foster R, Keogh JS: Molecular phylogeny and divergence dates for Australasian elapids and sea snakes (Hydrophiinae): evidence from seven genes for rapid evolutionary radiations. J Evol Biol 2008, 21:682–695. 180. Sanders KL, Lee MSY: Molecular evidence for a rapid late-Miocene radiation of Australasian venomous snakes (Elapidae, Colubroidea). Mol Phylogenet Evol 2008, 46:1165–1173. 181. Chen X, Huang S, Guo P, Colli GR, de Oca AN M, Vitt LJ, Pyron RA, Burbrink FT: Understanding the formation of ancient intertropical disjunct distributions using Asian and Neotropical hinged-teeth snakes (Sibynophis and Scaphiodontophis: Serpentes: Colubridae). Mol Phylogenet Evol 2012, 66:254–261. 182. Huang S, Liu SY, Guo P, Zhang YP, Zhao EM: What are the closest relatives of the hot-spring snakes (Colubridae, Thermophis), the relict species endemic to the Tibetan Plateau? Mol Phylogenet Evol 2009, 51:438–446. 183. He M, Feng JC, Liu SY, Guo P, Zhao EM: The phylogenetic position of Thermophis (Serpentes: Colubridae), an endemic snake from the Qinghai-Xizang Plateau, China. J Nat Hist 2009, 43:479–488. 184. Socha JJ: Gliding flight in Chrysopelea: turning a snake into a wing. Integr Comp Biol 2011, 51:969–982. 185. Helfenberger N: Phylogenetic relationship of Old World ratsnakes based on visceral organ topography, osteology, and allozyme variation. Russ J Herp 2001, 8:1–56. 186. Alfaro ME, Arnold SJ: Molecular systematics and evolution of Regina and the Thamnophiine snakes. Mol Phylogenet Evol 2001, 21:408–423. 187. de Queiroz A, Lawson R, Lemos-Espinal JA: Phylogenetic relationships of North American garter snakes (Thamnophis) based on four mitochondrial genes: How much DNA sequence is enough? Mol Phylogenet Evol 2002, 22:315–329. 188. Cope ED: Eleventh contribution to the herpetology of tropical America: Dugés, A. Proc Amer Philos Soc 1879, 18:261–277. 189. Fitzinger L: Systema Reptilium. Fasciculus Primus, Amblyglossae. Vienna: Apud Braumüller and Seidel Bibliopolas; 1843. 190. Vidal N, Dewynter M, Gower DJ: Dissecting the major American snake radiation: a molecular phylogeny of the Dipsadidae Bonaparte (Serpentes, Caenophidia). CR Biol 2010, 333:48–55. 191. Caldwell MW: Squamate phylogeny and the relationships of snakes and mosasauroids. Zool J Linn Soc 1999, 125:115–147. 192. Heath TA, Hedtke SM, Hillis DM: Taxon sampling and the accuracy of phylogenetic analyses. J Syst Evol 2008, 46:239–257. 193. Hedtke SM, Townsend TM, Hillis DM: Resolution of phylogenetic conflict in large data sets by increased taxon sampling. Syst Biol 2006, 55:522–529. Pyron et al. BMC Evolutionary Biology 2013, 13:93 http://www.biomedcentral.com/1471-2148/13/93 Page 53 of 53 194. Rannala B, Huelsenbeck JP, Yang ZH, Nielsen R: Taxon sampling and the accuracy of large phylogenies. Syst Biol 1998, 47:702–710. 195. Poe S, Swofford DL: Taxon sampling revisited. Nature 1999, 398:299–300. 196. Fisher-Reid MC, Wiens JJ: What are the consequences of combining nuclear and mitochondrial data for phylogenetic analysis? Lessons from Plethodon salamanders and 13 other vertebrate clades. BMC Evol Biol 2011, 11:300. 197. McMahon MM, Sanderson MJ: Phylogenetic supermatrix analysis of GenBank sequences from 2228 papilionoid legumes. Syst Biol 2006, 55:818–836. 198. Lemmon AR, Emme SA, Lemmon EM: Anchored hybrid enrichment for massively high-throughput phylogenomics. Syst Biol 2012, 61:727–744. 199. Faircloth BC, McCormack JE, Crawford NG, Harvey MG, Brumfield RT, Glenn TC: Ultraconserved elements anchor thousands of genetic markers spanning multiple evolutionary timescales. Syst Biol 2012, 61:717–726. 200. Crawford NG, Faircloth BC, McCormack JE, Brumfield D, Winker K, Glenn TC: More than 1000 ultraconserved elements provide evidence that turtles are the sister group of archosaurs. Biol Lett 2012, 8:783–786. 201. Edwards SV, Liu L, Pearl DK: High-resolution species trees without concatenation. Proc Natl Acad Sci USA 2007, 104:5936–5941. 202. Heled J, Drummond AJ: Bayesian inference of species trees from multilocus data. Mol Biol Evol 2010, 27:570–580. 203. Ricklefs RE, Losos JB, Townsend TM: Evolutionary diversification of clades of squamate reptiles. J Evol Biol 2007, 20:1751–1762. 204. Brandley MC, Huelsenbeck JP, Wiens JJ: Rates and patterns in the evolution of snake-like body form in squamate reptiles: evidence for repeated re-evolution of lost digits and long-term persistence of intermediate body forms. Evolution 2008, 62:2042–2064. 205. Pyron RA, Burbrink FT: Systematics of the Common Kingsnake (Lampropeltis getula; Serpentes: Colubridae) and the burden of heritage in taxonomy. Zootaxa 2009, 2241:22–32. 206. Pyron RA: A likelihood method for assessing molecular divergence time estimates and the placement of fossil calibrations. Syst Biol 2010, 59:185–194. 207. Edgar RC: MUSCLE: multiple sequence alignment with high accuracy and high throughput. Nucleic Acids Res 2004, 32:1792–1797. 208. Larkin MA, Blackshields G, Brown NP, Chenna R, McGettigan PA, McWilliam H, Valentin F, Wallace IM, Wilm A, Lopez R, et al: Clustal W and Clustal X version 2.0. Bioinformatics 2007, 23:2947–2948. 209. Stamatakis A, Aberer AJ, Goll C, Smith SA, Berger SA, Izquierdo-Carrasco F: RAxML-Light: a tool for computing terabyte phylogenies. Bioinformatics 2012, 28:2064–2066. 210. Stamatakis A: RAxML-VI-HPC: maximum likelihood-based phylogenetic analyses with thousands of taxa and mixed models. Bioinformatics 2006, 22:2688–2690. 211. Felsenstein J: Inferring Phylogenies. Sunderland: Sinauer Associates; 2004. 212. Anisimova M, Gil M, Dufayard JF, Dessimoz C, Gascuel O: Survey of branch support methods demonstrates accuracy, power, and robustness of fast likelihood-based approximation schemes. Syst Biol 2011, 60:685–699. 213. Guindon S, Dufayard JF, Lefort V, Anisimova M, Hordijk W, Gascuel O: New algorithms and methods to estimate maximum-likelihood phylogenies: assessing the performance of PhyML 3.0. Syst Biol 2010, 59:307–321. 214. Schneider JG: Historiae Amphibiorum Naturalis et Literariae. Fasciculus Secundus continens Crocodilos, Scincos, Chamaesauras, Boas, Pseudoboas, Elapes, Angues, Amphisbaenas et Caecilias. Jena: Frommani; 1801. 215. McDowell SB: A catalog of the snakes of New Guinea and the Solomons, with special reference to those in the Bernice P. Bishop museum. Part III. Boinae and Acrochordoidea (Reptilia, Serpentes). J Herp 1979, 13:1–92. doi:10.1186/1471-2148-13-93 Cite this article as: Pyron et al.: A phylogeny and revised classification of Squamata, including 4161 species of lizards and snakes. BMC Evolutionary Biology 2013 13:93. Submit your next manuscript to BioMed Central and take full advantage of: • Convenient online submission • Thorough peer review • No space constraints or color figure charges • Immediate publication on acceptance • Inclusion in PubMed, CAS, Scopus and Google Scholar • Research which is freely available for redistribution Submit your manuscript at www.biomedcentral.com/submit