Mayflies and stoneflies

Transcription

Mayflies and stoneflies
MODULE 4: ADVANCED IDENTIFICATION OF
MAYFLIES (EPHEMEROPTERA) AND
STONEFLIES (PLECOPTERA)
- BY CRAIG MACADAM
Introduction to this module
Mayflies and stoneflies are relatively small
groups of organisms with 51 and 39 species
respectively. Whilst on the surface they may
seem difficult groups to ID, there are a number
of shortcuts that can help with their
identification. A number of the species were
described in Module 2, and there is a certain
amount of reiteration. This module will cover
the species for which close examination of fine
features or dissection becomes necessary.
As with the first three Modules, there are mandatory exercises, which will
be marked by your tutor. You can submit them by printing out this
workbook and filling in the appropriate spaces by hand (but please add
your name to the front of the workbook), or you can use the template
appended to the introductory part and send completed exercises by email.
Completion of this module will give you the Advanced Level for
identification of mayflies and stoneflies.
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SECTION 1: MAYFLIES (EPHEMEROPTERA)
For this section, you'll need a copy of the FBA key to the Larvae of the
British Ephemeroptera: Scientific Publication no. 49 (Elliott, Humpesch
and Macan, 1988). N.B. You should note that this key is now well out of
date, and does not include Electrogena affinis, Caenis beskidensis or
C. pseudorivulorum. To identify these species you will have to consult
the following papers:
•
Blackburn, J.H., Gunn R.J.M. & Hammett, M.J. (1998).
Electrogena affinis (Eaton, 1885) (Ephemeroptera,
Heptageniidae), a mayfly new to Britain. Entomologist's
Monthly Magazine. 134 :257-263.
• Gunn R.J.M. & Blackburn J.H. (1998). Caenis beskidensis Sowa
(Ephemeroptera, Caenidae), a mayfly new to Britain.
Entomologist's Monthly Magazine. 134 :94
• Gunn R.J.M. & Blackburn J.H. (1997). Caenis pseudorivulorum
Keffermüller (Ephem., Caenidae), a mayfly new to Britain.
Entomologist's Monthly Magazine. 133 :97-100.
Having completed Module 2, you will be aware that the Ephemeroptera
fauna consists of only 51 species. The Ephemeridae, Ephemerellidae,
Potamanthidae and Ameletidae were covered in Module 2 so we won’t
cover them again here.
To recap, the features you need to use to separate virtually all of them are:
1.
Gills (number, arrangement/position and shape);
2.
General colour (and distribution of pigment, if any);
3.
Shape (including presence of spines on the abdomen and
‘positioning’ of antennae);
4.
Colour, length and ‘positioning’ of tails
It is important when handling Ephemeroptera larvae that you lift them by the
legs. This prevents damage to the tails or gills that are important diagnostic
features. This method also gives six opportunities to successfully lift the
specimen! The opposite is the case for Plecoptera larvae where the tarsal
arrangement is important – try and lift these by the body.
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SECTION 1: CONTINUED
Baetidae
Many workers say the Baetidae fill them with dread as the FBA key advises
you to look at the mouthparts, however there are plenty of ‘jizz’ features
that can help you make the identification. There are three main groups of
Baetidae. First you can separate them into specimens with the middle tail
much shorter than the outer tails or with a middle tail about the same size
as the other tails.
The shorter middle tail is characteristic of Baetis spp. Species in this group
can be separated by their body shape into two groups - those with a wide
body and those with a narrow body. The best way to separate these
groups is to look at the antennae. In the narrow-bodied species the
antennae bases are close together in the centre of the head, while in the
wide-bodied species the antennae are wider apart (see Elliott, Humpesch
and Macan, p33 and mini-key below).
There are four narrow-bodied species – Baetis atrebatinus, B. muticus, B.
digitatus and B. niger. Of these, Baetis digitatus and B. niger have a dark
band across their tails and only six pairs of gills, whereas in Baetis muticus
and B. atrebatinus the tails are plain and there are seven pairs of gills.
Baetis muticus is unique in the British Baetidae - the right prostheca on the
mandible is absent and replaced with two bristles (see Elliott, Humpesch
and Macan, p35). Baetis atrebatinus is separated from all other Baetidae by
a protrusion on the outer edge of the basal segment of the antenna (look
carefully!!) and also the tip of the maxillary palp is concave – in all the other
Baetidae it is convex.
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SECTION 1: CONTINUED
Narrow-bodied larvae
Wide-bodied larvae
Antennae close together
Antennae wider apart
No black band on
tail (tips may be
darker)
Seven pairs* of
gills present.
Baetis muticus
Baetis
atrebatinus
Distinctive black
band on tails
Six pairs* of gills
present.
Baetis digitatus
Baetis niger
Distinctive black
band on tails
Baetis scambus
Baetis fuscatus
No black band on
tail (tips may be
darker)
Baetis rhodani
Baetis buceratus
Baetis vernus
*(It is important to check the number of gills carefully. In damaged specimens the
last (7th) pair of gills are often missing resulting in six pairs of gills being present. In
Baetis digitatus and B. niger, it is always the first gill that is absent. In mature
nymphs the 1st gill is sometimes hidden under the developing wing pads, or in the
case of Baetis muticus and Baetis atrebatinus the 1st gill is very small).
As explained above, Baetis digitatus and B. niger have a black band on
their tails, however their separation is tricky. One suggested feature to use
is the shape of the last gill which has a slightly concave hind margin in B.
digitatus, whereas in B. niger all the gills are oval (Elliott, et al., p41).
Another possible feature to use are the dark bands on the tails. In B.
digitatus there is one band in the middle of the tails which is relatively short.
B. niger has a second dark band at the base of the tails and the middle
band is longer, covering about a third of the length of the tails (Elliott, et al.,
p41). If you’re not sure then play safe and mark them down as Baetis niger/
digitatus or Baetis sp.
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SECTION 1: CONTINUED
Of the five Baetis spp., Baetis rhodani can be identified by the spines on the
edge of the gills, but remember that Ameletus inopinatus also has these
spines. Baetis scambus and B. fuscatus both have a black band on their
tails. You can use the pattern of lighter patches on the head to identify B.
scambus, however this pattern can be faint or absent in northern specimens.
If you do see these markings though you can be sure it is B. scambus,
otherwise you should mark it down as Baetis scambus/fuscatus. Baetis
buceratus has a series of white spots on the dorsal surface of each body
segment – really distinctive, and it is in the FBA key (p. 48) but it is rarely
used as an ID feature. That leaves any thing that doesn’t have spines, bands
or dots as Baetis vernus!
Until you get your eye in with these ‘jizz’ features it’s worth checking the
mouthparts (see Elliott, Humpesch and Macan, p35) to check your
identification.
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EXERCISE 1: DISSECT THE MOUTHPARTS OF A MAYFLY
This mandatory exercise is worth 10 points.
Take a Baetidae larva and dissect the
mouthparts. Using a mounted needle pick
out the individual mouthparts under a
stereo microscope. Place the individual
mouthparts onto a microscope slide and
cover with a cover slip.
There is an
alternative “quick and dirty” method –
place the larva in the centre of a
microscope slide and crush it with a
second slide to make a mayfly ‘sandwich’.
If you’re lucky the mouthparts will have splayed out and will be visible under
the microscope (see image on right). Obviously, only do this when the
specimen isn’t important!
Dissect the mouthparts and, in the space below, attach a photograph or
make a sketch of the individual parts. With reference to page 24 of Elliott,
et al., write down which species you think it is.
Complete exercise 1 in the space below or use the template appended to
the introductory leaflet.
Mark =
/ 10
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SECTION 1: CONTINUED
Continuing with the Baetidae, those with the middle tail roughly the same
length as the outer tails comprises Cloeon, Centroptilum and Procloeon.
There are two Cloeon species which have a dark band over the tails and
can be separated by the shape of the gills. In C. dipterum the double gills
are rounded at the tip and are both of a similar size. In C. simile the gills are
pointed at the tip and one of the double gills is much larger than the other.
These features are easier to see if you detach the gills from the body. Try
and take one from the middle of the larva as these are larger.
Gill of Cloeon dipterum
Gill of Centroptilum
luteolum
Centroptilum luteolum also has tails that are roughly the same length
however they never have a distinct dark band across the middle. To
separate C. luteolum from Cloeon and Procloeon species you must
examine the gills. C. luteolum has seven pairs of gills, each of which
consists of a single plate shaped like a beech leaf and with a pointed tip.
Procloeon bifidum also has seven pairs of single gills however the gills
never have a pointed tip.
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SECTION 1: CONTINUED
Six of the seven pairs of gills in Procloeon pennulatum consist of double
plates. The seventh pair has single plates. Both Cloeon simile and P.
pennulatum have one of the double plates much larger than the other,
however in C. simile the large plate has a pointed tip whereas in P.
pennulatum the larger plate is rounded. A further characteristic to separate
P. pennulatum from the British Cloeon species is the number of dark rings
on the tails. In P. pennulatum there are no more than five dark rings
between the body and the dark band on the tails, while in Cloeon species
there are more than 5 dark rings.
Finally, unlike other Baetidae, P.
pennulatum holds its tails very closely together when at rest.
Caenidae
More species groupings! Brachycercus harrisellus was covered in Module
2. Caenis beskidensis, C. pseudorivulorum and C. rivulorum are all
superficially similar and can be separated with care using the features in
Gunn and Blackburn, 1997 (see above).
If you’re not sure of the
identification they should be recorded as C. rivulorum group (it’s likely that
the specimen will be C. rivulorum, but not definite).
Caenis luctuosa and C. macrura can be separated from other Caenis
species by the presence of a deep notch in the underside of the last body
segment and the shape of the pronotum, which is broader near the head
and has either straight or slightly convex edges. Separation of nymphs of
C. luctuosa and C. macrura is particularly difficult and unreliable, although
some workers believe that differences in the coloration of the body
segments can be used to separate these species. Play on the safe side
and mark them down as Caenis luctuosa/macrura.
Notch on underside of last segment of Caenis luctuosa
Caenis horaria can be separated from other Caenis species by the shape of
the pronotum, which is broader near the head with slightly concave edges,
unlike those of other species, which are either straight or slightly convex.
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SECTION 1: CONTINUED
The identification of Caenis pusilla (by the book) relies on microscopic
examination of the spines on the body and bristles on the legs (see Elliott et
al., p76) but once you’ve seen a specimen you’ll recognise it straight away.
They are rather long larvae compared to other Caenis spp.
Caenis robusta can be separated from other Caenis species by the shape of
the pronotum, which has strong corners on the front edge and a light line
down the middle.
Heptageniidae
Module 2 explained how to identify the Heptageniidae to genus. Let’s start
our species ID with the Ecdyonurus. E. insignis is easily separated from the
other three British species by the presence of a pattern of dark markings on
the ventral surface of the abdomen and also the presence of a tuft of
filaments alongside the last gill. The other three species, E. dispar, E.
torrentis and E. venosus are all very similar. Elliott, et al., p52 explains that
these species can be separated by the shape of the pronotum and glossa
(part of the mouthparts – remember?), however you need to look at a large
number of specimens to convince yourself of the differences. There are
however a number of other ‘jizz’ features that may help. In E. venosus the
tarsi has a single dark band close to the claw, whereas in E. dispar and E.
torrentis the tarsi have a dark band both at the claw and next to the tibia.
E. torrentis often has a similar pattern of ventral markings as E. insignis,
however they are pale on a dark background in E. torrentis. If you’re not
confident of your identification of any of these three species you should
mark them down as Ecdyonurus venosus group.
Heptagenia sulphurea is the only Heptageniidae species with a
conspicuous black and white pattern on the body and annulated tails. So
far, so good. Heptagenia longicauda is superficially similar to H. sulphurea
but has only been recorded in the UK on four occasions – all in the Thames
catchment. It has plain tails and a pair of small bumps – one on either side
of the pronotum. If you think you’ve got a specimen of H. longicauda make
sure to get a second opinion and report it to the Ephemeroptera Recording
Scheme!!!
Electrogena has a pale cross shape on each femur and a long fringe of
hairs on the posterior edge of the femur. There are two species – E. lateralis
and E. affinis (the latter was found in the River Derwent, Yorkshire in 1988,
and it might be present in other watercourses). Features for the separation
of these species are available in Blackburn, Gunn and Hammett, 1998 (see
above). For the purposes of this workbook just mark them down as
Electrogena sp.
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SECTION 1: CONTINUED
As with the Ecdyonurus venosus group, the features used in the FBA key to
separate the Rhithrogena are very subtle and tend to require a large number
of specimens to be examined to be reliable. Some workers have suggested
that the shape of the femoral dot can be used to separate the species, but
this is untested at present. Large larvae collected in February and March
are likely to be R. germanica, large specimens collected in May and June
are likely to be R. semicolorata. At other times of the year they should be
recorded as Rhithrogena sp.
Femur of Rhithrogena showing
reddish ‘dot’.
Femur of Electrogena showing
pale cross.
The last species to be considered under the Heptageniidae is Kageronia
fuscogrisea. This is a highly localised species found mainly in Ireland and
Dumfries and Galloway but also occasionally in the Thames catchment.
Fresh specimens are reddish in colour and they have very distinctive gills
which are produced into points.
Arthropleidae
As you saw in Module 2 - Arthroplea congener has distinctive maxillary
palps and is very rare.
New evidence from Europe suggests that this
species is not only found in streams but also in small ponds. So it may still
turn up in this country as there has not been an extensive survey of ponds
for this species (a long shot perhaps!).
Leptophlebidae
The Leptophlebiidae are easy to take to genus. As you’ve seen in Module
2, Habrophlebia has multiple branching gills, like little trees. However keep
an eye out for the possibility of European species turning up in the UK.
Thraulus spp. are similar to Habrophlebia but the first gill is made up of two
simple branches (like a letter ‘Y’ or a tuning fork). Other European species
of Habrophlebia might also appear in the UK. Habrophlebia fusca has 2 to
4 filaments on the small branch of gills 2 to 6. If you suspect you’ve got a
different Habrophlebia sp. or Thraulus sp. then get in touch with the
Ephemeroptera Recording Scheme (contact details at the end of this
workbook).
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SECTION 1: CONTINUED
The gills of Paraleptophlebia are like little letter ‘Y’s or tuning forks. Be
careful because immature Leptophlebia also have gills like this before the
flattened plate develops. So if you’ve got a small specimen (<3mm) or the
gills are damaged you’ll have to look at the mouthparts. In Leptophlebia
the maxillary palp is shorter than the maxilla, whereas in Paraleptophlebia
the maxillary palp is longer than the maxilla (see Elliott, et al., p63).
The gills of Paraleptophlebia spp. are readily lost from larvae once they’ve
been sloshed about in a sample. As a result you’ll have to look at the
coverage of teeth on the claws and the shape of the bristles on the femur to
make an identification (Elliott, et al., p66). If you think you’ve got a
specimen of Paraleptophlebia werneri then you’re either really lucky (it’s a
highly localised species of winterbournes and ditches), or more likely,
you’ve got an immature specimen of Leptophlebia marginata - look again at
the mouthparts to separate the genera.
Gills of Leptophlebia marginata
Teeth covering ¾ of claw on
L. marginata.
To separate the two Leptophlebia spp. take a look at the gills. In L.
vespertina the wide part of the gills tapers gradually towards the tip. In L.
marginata the wide part ends abruptly about halfway along the gill. To
confirm the identification take a look at the claws – if the teeth cover nearly
the whole length of the claw it’s L. vespertina, if they stop short (3/4 along
the claw) it’s L. marginata. If you really want to be sure check the bristles
on the femur (see Elliott, et al., p64).
Siphlonuridae
The Siphlonuridae have large larvae when mature. Immature specimens are
superficially similar to Cloeon species, however the Siphlonurids have large
spines projecting from the rear corners of each body segment.
Heptageniidae and Ephemerellidae also have spines on the body segments
however they never have any double plate-like gills along their body.
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SECTION 1: CONTINUED
Spines on abdominal segments of
Siphlonurus lacustris showing the dark mark
So if you’re happy that you have a Siphlonurus spp., have a look at the
number of double gills. In S. alternatus there are six pairs of double gills,
whereas in S. armatus and S. lacustris only the first two pairs of gills are
double. You can separate S. armatus and S. lacustris by the presence of
dark marks on the lateral margins of abdominal segments 2 to 9 (at least on
segments 8 and 9) in S. lacustris. If you’re working with a long preserved
specimen that has lost it’s colouration you’ll have to look at the mouthparts
(see Elliott, et al., p24).
So that's it for the mayflies. We'll now move on to a closely related order of
invertebrates – the Stoneflies or Plecoptera.
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EXERCISE 2: IDENTIFY A PRESERVED MAYFLY
This mandatory exercise is worth 10 points.
Find a preserved mayfly of any family. In the space below, either attach a
photograph (or more than one, if necessary) or make a sketch of your
specimen. The sketch needn't be of the whole animal, just the diagnostic
features, if you wish. Write down which species (or species group) you
think it is. Also write down why you believe it to be this species (your
'diagnosis'), with arrows pointing to the relevant bits if you feel it necessary
to do so.
Complete exercise 2 in the space below or use the template appended to
the introductory leaflet.
Mark =
/ 10
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SECTION 2: STONEFLIES (PLECOPTERA)
For this section, you'll need a copy of the FBA key to the Adults and
Nymphs of the British Stoneflies: Scientific Publication no. 17 (Hynes,
1977).
As with the mayflies, the stoneflies are a relatively small order of insects
with only 39 species in the UK. The Perlidae and Chloroperlidae were
covered in Module 2 so we won’t cover them again here. To recap, the
features used to identify stoneflies are as follows:
1.
Presence of gills;
2.
Various sutures on the cuticle;
3.
Arrangements of hairs and bristles;
Taeniopterygidae
We’ve already met the ‘Stegosaurus stonefly’ Taeniopteryx nebulosa in
module 2. There are 3 other Taeniopterygidae species in the UK. The
rarest of these is Rhabdiopteryx acuminata. This species is generally
thought to be restricted to rivers in Yorkshire, Radnorshire and
Montgomeryshire however there are occasional records from other parts of
the UK which deserve further investigation. R. acuminata can be separated
from the Brachyptera spp. by the absence of upright hairs on the tails and
last few abdominal segments. Make sure to take a look at the specimen
from the side.
The two Brachyptera spp. can be separated by the
colouration of the tarsus and tibia. In B. risi the tarsus is dark and the tibia
is plain with no dark patches. In B. putata the tarsus is pale and the tibia
has a dark patch at the base. B. risi is by far the most common of these
species, with B. putata restricted to the Scottish Highlands and the River
Wye upstream of Monmouth. B. risi prefers small stony streams and
occasionally larger rivers where it can be found in mosses. B. putata is a
UK BAP species which is (currently) thought to be endemic to the British
Isles.
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SECTION 2: CONTINUED
Plain tibia and darkened tarsi of Brachyptera risi
Nemouridae
In module 2 we saw how to separate the Nemouridae into genera.
Unfortunately (or fortunately depending on your outlook) there are a number
of problems with separating the species of Protonemura and Nemoura.
Protonemura meyeri can be identified by looking at the tarsi. The upperside
of the tarsus is darkened in P. meyeri whereas in P. montana and P. praecox
it is uniformly pale. P. montana and P. praecox are difficult to separate and
should probably be left as P. montana/praecox. It’s worth noting that
Protonemura are not generally found in the south east of England. In
addition, Protonemura montana is typically found above 518 metres (1700
feet), however remember in both these cases there are always exceptions
and you might be just the person to discover something new about this
genus!
Amphinemura sulcicollis and A. standfussi are quite easy to separate. A.
sulcicollis has a distinct patch of long bristles towards the far end of the
femur. These bristles are often fouled up with pieces of silt and other
detritus. This group of bristles is absent in A. standfussi, instead there are
shorter bristles across the whole of the femur.
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SECTION 2: CONTINUED
Long femoral bristles on Amphinemura sulcicollis
To separate Nemurella picteti from other Nemoura spp. have a look at the
tarsus. In N. picteti segments 1 and 3 are almost equal in length. In
Nemoura spp. the third segment is much longer than the first. In smaller
specimens this doesn’t work as well, however you can still separate
Nemurella picteti which has a row of long bristles about ¾ along the femur
(see Hynes, p. 61).
Of the Nemoura spp. you can easily separate N. avicularis from other
species by looking at the second segment of the antenna which is
completely dark. Unfortunately the separation of the other species is rather
subjective. N. cambrica and N. erratica are squatter, more stout bodied
than N. cinerea and N. dubitans. In N. cambrica/erratica the hind tibia is 6
to 8 times as long as wide while in N. cinerea/dubitans it is 9 to 11 times as
long as wide. Separating the species in these groups is difficult and
unreliable.
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SECTION 2: CONTINUED
Perlodidae
The key for Perlodidae is rather uniniviting with close examination of the
mouthparts a must. Let’s try and bypass this stage – for your own sanity!
Perlodes microcephalus can be identified by body segments one to four
having separate tergites and sternites. The other Perlodidae only ever have
segment one and two separated like this. Isoperla grammatica and I.
obscura are densely covered in black clothing hairs – a dead giveaway. I.
obscura was once found in the River Trent near Nottingham, however it is
now thought to be extinct. If you think you’ve found a specimen of I.
obscura then the chances are that it’s actually I. grammatica – double check
the mouthparts as described in Hynes, 1977 (page 72-76) to make sure.
Black clothing hairs on
Isoperla grammatica
Diura bicaudata doesn’t have any clothing hairs at all, while Isogenus
nubecula is covered in pale clothing hairs. I. nubecula is a UK BAP species
which was thought to be extinct, but was recently re-discovered in the
Welsh River Dee. However, despite extensive surveys in 2005/06 it hasn’t
been found again.
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EXERCISE 3: DISSECT THE MOUTHPARTS OF A
PERLODIDAE STONEFLY
This mandatory exercise is worth 10 points.
Take a Perlodidae larva and dissect the mouthparts. Using a mounted
needle pick out the individual mouthparts under a stereo microscope.
Place the individual mouthparts onto a microscope slide and cover with a
cover slip.
In the space below, attach a photograph or make a sketch of the individual
parts. With reference to page 72-76 of Hynes, 1977 write down which
species you think it is.
Complete exercise 3 in the space below or use the template appended to
the introductory leaflet.
Mark =
/ 10
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SECTION 2: CONTINUED
Leuctridae
You’ve already seen how to separate the rather ‘goaty’ looking Leuctra
geniculata and the hairy L. nigra from other Leuctridae. One thing to note
though – it’s possible to confuse Leuctra nigra with Chloroperla torrentium –
both species have hairy pronotums, however if you check the tarsal
arrangement and the shape of the wing pads, these two species are easily
separated. Once these two are out of the way Leuctra fusca is relatively
easy to separate from the remaining species as it has a long fringe of hairs
on the posterior edge of the tibia. Specimens without this long fringe of
hairs include L. inermis, L. hippopus and L. moselyi. Leuctra inermis has a
series of long bristles on the dorsal surface of the body. There should be at
least one pair, sometimes more, on segments 2 to 10. Be careful to make
sure you are looking at the dorsal surface. Sometimes the abdomen
detaches slightly from the thorax and can be rotated so that the dorsal
surface is actually at the side, however the bristles are still really easy to
see. The remaining two species are difficult and unreliable to separate so
should be recorded as L. hippopus/moselyi.
Capniidae
The Capniidae superficially look like the Leuctridae but once you’ve seen a
few they’re unmistakeable. Capnia atra has long hairs on the tails so that in
the middle of the tail they are longer than the tail segment. In C. bifrons and
C. vidua they are always shorter than the tail segments. The features to
separate C. bifrons and C. vidua are quite subtle. The most reliable uses
the bristles on the femur. In C. bifrons the bristles on the posterior edge of
the femur are relatively long, whereas in C. vidua they are similar in length to
those on the anterior edge (see Hynes 1977, p. 70).
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EXERCISE 4: IDENTIFY A PRESERVED STONEFLY
This mandatory exercise is worth 10 points.
Find a preserved stonefly of any family. In the space below, either attach a
photograph (or more than one, if necessary) or make a sketch of your
specimen. The sketch needn't be of the whole animal, just the diagnostic
features, if you wish. Write down which species you think it is (or species
group). Also write down why you believe it to be this species (your
'diagnosis'), with arrows pointing to the relevant bits if you feel it necessary
to do so.
Complete exercise 4 in the space below or use the template appended to
the introductory leaflet.
Mark =
/ 10
Module 4: Version 3, December 2007 (Craig Macadam)
Page 21 of 21
Section 2: Continued
Hooray - you've finished! Your final mark is written in the box below. Now,
why don't you try out the next Module (5) and get to grips with Caddisflies.
/ 40 =
%: Pass
Fail
For more information on the British Ephemeroptera or to report a rare
species contact:
Ephemeroptera Recording Scheme
c/o Buglife Scotland
Balallan House
24 Allan Park
Stirling
FK8 2QG
Email: info@ephemeroptera.org.uk
Tel: 07786 631369
Module 4: Version 3, December 2007 (Craig Macadam)