Running a moth-trap provides a window
into many other insect groups because the attraction to light is not limited
solely to moths. Although it is
impossible to do justice to everything, if time permits I do try my best to identify
things which appear to me to be noteworthy, especially if I haven’t seen them
before. While this often means the
larger or more spectacular-looking moth-trap visitors, it is by no means
limited entirely to them. Beetles probably
offer the best chance of successful identification and regulars such as
Cockchafer Melolontha melolontha,
Summer Chafer Amphimallon solstitiale
, Black Snail Beetle Silpha atrata and the very smelly Sexton Beetles are easy enough to identify by anyone. A few of the water beetles, of which Colymbetes fuscus and the very large Dytiscus marginalis seem to me to be the most regular moth-trap visitors in Bucks, can be identified with care. Most Ladybirds can be identified safely to species and our three largest Carabus
ground beetles, which sometimes creep up to the light looking for an easy meal, can
also be separated quite easily.
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Common Cockchafer Melolontha melolontha |
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Eyed Ladybird Anatis ocellata, Stoke Common 15th May |
|
Bronze Ground Beetle Carabus nemoralis consuming a
Small Brindled Beauty, Bernwood Forest 20th March |
Other groups which will be familiar
to all light-trappers include the trichoptera (caddis flies), of which there
are some 200 species in the UK and Ireland and about half that number are known from Bucks.
In the right habitat at the right time of year they can sometimes outnumber
the moths. Few are recognisable solely
by their shape or markings but one which
can be recorded safely on sight is Glyphotaelius
pellucidus with its distinct tornal notch. The largest British caddis species is
Phryganea grandis and a combination
of sheer size and wing markings led me to that ID
for the female illustrated below, which came to light on Coombe Hill on 5th July 2017, although one has to be careful to
eliminate the rather similar Phryganea
unipuncta (sometimes only possible through inspection of the genitalia).
|
Caddis Glyphotaelius pellucidus, Westcott 16th April |
|
Caddis Phryganea grandis, Coombe Hill 5th July |
Amongst the hymenoptera, many
moth-trappers will no doubt be familiar enough with the Hornet Vespa crabro although other members of this group are nowhere near
as easy to identify. The mostly orange nocturnal
ichneumonid wasps are regular visitors to light traps but unfortunately very
few of them can be identified to species level without using a microscope. Ophion
obscuratus is the obvious exception, with its creamy-white stripes on the thorax,
but there are other nondescript species (such as the early spring example below,
Ophion scutellaris with its very long
antennae) which can be identified with care and there are keys as well as the
services of various experts which can be called upon if one is prepared to make
the effort to pursue them further - and your records will always be very well
received.
|
Ichneumonid Wasp Ophion scutellaris, Westcott 11th March |
A small selection of the many other light-trap
visitors which I managed to identify during 2017 is illustrated below:
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False Blister Beetle Oedemera femoralis, Coombe Hill 9th April |
|
Long-horn Beetle Stenocorus meridianus, Bernwood 10th June |
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Emperor Dragonfly Anax imperator, Westcott 23rd June |
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Downland Bee-fly Villa cingulata, Hog Wood 26th June |
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Tanner Beetle Prionus coriarius, Hog Wood 17th July |
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Eared Leafhopper Ledra aurita, Westcott 7th September |
|
Beetle Chrysolina banksii, Finemere Wood 22nd December |
Other groups such as lacewings,
harvestmen and spiders appear frequently at light traps and identifications can
be pursued either through on-line keys, via iSpot or the iRecord app or else through their various recording schemes, although in many
cases a specimen will be required as it is not always possible to confirm the
species from a photograph.
Of course, being able to name these insects
is not the end of the matter and, once the correct identification has been verified, it is equally as important to ensure that the
information does at the very least find its way to your local environmental records
centre!
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