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"A Nature Observer's Scrapbook"

Other Insects



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Adult Lacewing Lacewing larval stages

Green Lacewing

Chrysopa carnea (agg)

The suffix 'agg', short for aggregate, is used to indicate a 'Super species' group of several distinct species which appear to be superficially similar. Of the 14 different species of British green lacewings, Chrysopa carnea agg is the most common. Overall body length is about 12 - 15mm.

Chrysopa carnea hibernates as an adult insect during the winter and is often found indoors, whereas many other lacewing species hibernate as larvae. The adult in the upper image was found indoors in November.

When the adults emerge from hibernation, they will survive on nectar and pollen but, will subsequently join their larvae in targetting their favourite diet, the aphid. Claims are made that one Lacewing can consume up to 600 aphids in its lifetime. In some parts of the world Lacewings have been used to biologically control aphid populations.

However, the first larvae to hatch are just as likely to start their carnivorous life off by eating the other unhatched eggs in the clutch. Which seems very much at odds with the 'calm, delicate, sedate' appearance of the adult lacewing.


The lower composite image of the larval stages (not to scale) gives an indication of how the larvae develop.


The tiny black specimens were only about 4mm long and had accumulated a very effective camouflage by covering themselves in tiny paricles of soil and detrius.


The pale larva on the leaf had obviously climbed onto foliage and would be hunting for it's staple diet of aphids. This was about 8mm long.


The lower image of a more mature specimen, (possibly third and final stage larva) was 13mm long. It will be seen that in all stages of development they are equipped with substantial pincers, indicating their consistent carnivorous diet and carry a coat of stiff bristles that presumably make them less attractive to bird predators.



DateSighting
02.06.2003Larva by pondside in back garden.
04.04.2004Adults emerging from indoor hibernation.
18.08.20042nd generation larva searching for aphids on ditch-side vegetation.
14.09.20053rd stage larva on rose bush
14.11.2005Adult seeking an indoor hibernation refuge.
30.11.2005Hardy adult found outdoors on a very chill, rainy day.
03.08.20062nd stage larva feeding on aphids.
11.05.20121st stage larvae found in soil at base of rose bush.



Brown Lacewing Brown Lacewing wing detail

Brown Lacewing

Hemerobius sp.

At first, I mistook this for 'just another midge' silhouetted on the window before I noticed that the wings were folded 'tent like' over the body. That prompted me to take a second look and then it became apparent that it was a small lacewing (body length about 8mm).

It was only when the photograph was enlarged that the delicate tracery of the wing veins emphasised why they are called 'Lacewings'. There are a large number of genera and species in the 'Brown Lacewing' category and identification is extremely difficult. In this case, the clue to the Hemerobius genus is seen in the short veins on the leading edge of the wing, that are characteristically 'forked'.

Like the Green Lacewings, their better known relatives, their food of choice are aphids. The larvae are also similar but smaller and slimmer.



DateSighting
27.04.2008 Found silhouetted on a window.


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Scorpion Fly - male Scorpion Fly - female

Scorpion Fly

Panorpa communis,
.......... P. germanica,
.................. P. cognata

There are over 240 species of Scorpion Fly to be found in the Northern hemisphere. With four wings (fore and hind wings usually overlap closely when at rest), they are not considered to be 'true two winged flies' of the order Diptera. Scorpion Flies belong to the order, Insecta: Mecoptera: Panorpidae. They are closely related to Lacewings. Only three species of Scorpion Fly are resident in the UK - Panorpa communis, P. germanica and P. cognata. The first two look superficially very similar - so much so that close examinatiion is required to separate them. P. cognata, the smallest and least common tends to have pale sparsely marked wings and can have a reddish head.

Separating males from females is relatively easy. The upper image is of a male illustrating how the last three segments of the abdomen, comprising the reddish brown clasping organs, are reflexed up and forward, scorpion like - giving rise to the common name. The second image is of a female, showing the slim tapering abdomen which curves only gently upward.

It's tempting to try to identify the different species by wing patterns but there can be significant variation of pattern and colour intensity, not only through wear and tear but also when the transparent fore and hind wings don't overlap precisely, then the apparent pattern will appear to alter, leading to unreliable pattern recognition.

The males do offer a species specific clue to identity. The uppermost surface of the upturned scorpion-like, reddish brown coloured, clasping organ is marked in a species specific fashion. But, the differences are subtle and short of having examples of each species to compare a new specimen against, it would take a brave man (or an expert) to come to a conclusive determination. So, if it is difficult to identify a specimen when ideally placed in front of you, It is even more difficult to obtain species identification from a photograph when the lighting or angle of the shot may not be optimum. Intrusive microscopy may then be the only sure way to identify the species. The females do not offer any such species specific clues and accurate identification is often only possible by intrusive microscopy.

P. communis is, I think, generally found to be the largest species and P. cognata the smallest but, size varies within each species so that is no discriminator either. All Scorpion Flies tend to favour shaded areas. They are often found in hedgerows and wooded places from Spring to Autumn. While the adults may prey upon small insects, both adults and larvae will also scavenge on dead plant and animal matter. The larvae are caterpillar-like, with six thoracic legs but no prolegs. They emerge from eggs laid underground and will remain there until pupation and emergence as mature insects.


DateSighting
23.06.2003Female seen on hawthorn hedge.
05.06.2004Seen in SW corner of the Hay Meadow hawthorn hedge.
19.06.2005Male found posing on the garage wall.
03.07.2005Female found on Night Scented Stock in back garden at 16.00hrs.
14.06.2006Many found on Southern and Western hedges of meadow.
07.07.2008Found in Western hedge of meadow.
04.06.2009Three females seen on widely separated hawthorn hedging.
14.09.2016Male attracted to light at night. Forewing = 11mm.


Caddis fly,
Halesus radiatus Caddis fly,
Halesus radiatus

Caddis fly - 1

Halesus radiatus

There are as many as 400 different European Caddis fly species with forewings ranging in length from 7mm to 30mm. All carry their wings 'tent-like' over the body, all have long antennae (some, 3x the length of head and wings) and all have aquatic larvae.

Having so many species to choose from, it takes very detailed examination to positively identify any specific species. But, from the wing venation of these images, they appear representative of H. radiatus.

Halesus radiatus has a forewing length of about 20 - 22mm. It is on the wing from August to November and breeds in moving water. These specimens probably came from a nearby drainage ditch. In the case of the lower image, the ditch had only recently retained flowing water from the autumn rains and I presume this Caddisfly had recently emerged from pupation which could explain the very fresh, almost varnished appearance of the wings.

The soft bodied larvae of the different species construct unique protective 'cases' or silken webs around themselves that can be quite elaborate. This one builds up an inner tube of silk, stiffens that with three external slender twigs and then camouflages the whole with little pieces of plant debris, stuck on with salivary 'glue'. Others build cylindrical pots out of grains of sand or stone fragments.

With only their head and feet protruding from the case, the larvae use hooks at the end of their abdomen to latch on to the silken lining and drag the case, like a crab does it's shell, in their quest for food. Only prior to the state of pupation will the case be anchored to a stone or vegetation.

The adults may drink but are not known to feed. The larvae, on the other hand, are omnivorous and will take both small aquatic animals and plant material.



DateSighting
06.10.2005 Adult fly found on the front door about 15 yards from a wet ditch.
29.10.2008 Adult fly found on an outside window.


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Caddis fly,
Micropterna sequax Caddis fly larva,
Micropterna sequax

Caddis fly - 2

Micropterna sequax,
aka M. affinis,
...... M. lateralis,
...... M. taeniata,
...... Stenophylax sequax

Quite apart from all it's various synonyms, there are several very similar species so, the best that can be said is that the image is representative of Micropterna sequax. The wing venation looks right but I cannot vouch for the spines on the legs that are one of the critical identification features.

The normal flight period would be expected to be between May and November but, I have found them on the wing in a not noticeably mild February.

Like many insects, they can feign death when disturbed and will calmly flop on to their side. But, even when in a normal posture, they can be very placid and will pose for the camera much better than most other insects.

The three caddis flies described on the website all belong to the Limnephilidae family and it is characteristic that their larvae all construct tubular cases for protection but, each species creates its tube in a distinctive way. This one is formed from sand grains and small pebbles, others may be made from vegetation or a mix of materials. This one was found on the underside of a submerged piece of bark and had a silken lifeline attached to prevent it being swept away.

The larva has tiny claws on its soft abdomen with which it drags its case around when it is foraging for food - decayed plant or animal material.



DateSighting
15.02.2006 Found alive and well in garage, after dark.
29.03.2007 Larva found on a submerged piece of tree bark in water filled ditch..
05.06.2009 Adult attracted to light at night.


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Limnephilus lunatus,
caddis fly

Caddis fly - 3

Limnephilus lunatus

At last, a caddis fly with distinctive features. The coloration may vary from pale to dark brown but, the distinguishing feature is the pale 'half moon' on the rear margin of the wing - from whence the Latin 'lunatus'.

This is a cosmopolitan species to be found in all kinds of fresh water environments and can be 'on the wing' from May to November.

The larval case is constructed from leaf fragments, sand grains and other debris.



DateSighting
05.08.2006 Two specimens found within three days on vegetation by wet ditch.


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Lesser Marsh Grasshopper Lesser Marsh Grasshopper

Lesser marsh grasshopper

Chorthippus albo-marginatus


When trying to identify this one, I was surprised to find that there are nine or more different British grasshopper species, of which five are to be found in Lincolnshire.


Anyone who has tried to watch - or catch, a grasshopper will know that they are quite nervous and do not generally sit still for long. But, I was fortunate to rescue the upper one from a water trough and it was obviously exhausted from it's swim, so I was able to get several close shots before it sought cover in the grasses.


The clue to this species' identity lies in the almost parallel ridges or keels on the pronotum region behind the head (arrowed in the upper image). Other species tend to have a waisted or 'hour-glass' shaped pronotum.


This species comes in various colour forms, green, brown and straw colours being the most usual. And the females can have a prominent white streak on the leading edge of the forewing (as the scientific name suggests).


Mature adults can be 24mm long but an immature nymph, with characteristically 'rolled up' leading edges to the wings, was found measuring 16mm. The species tends to frequent damp low lying meadows and marshes.



DateSighting
01.09.2004 Northern end of hay meadow, rescued from the sheep water trough.
08.08.2005 Same area as last years specimen but greener.
14.08.2008 16mm nymph found by pond in Horncastle Community Woodland area.
17.09.2008 Found in long coarse grass at the base of a south facing wall.


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Slender Groundhopper Slender Groundhopper

Slender Groundhopper

Tetrix subulata

The two groundhopper species found in Lincolnshire, the 'Common' and the 'Slender groundhopper', have a broad-shouldered look about them compared to the larger grasshoppers. They are readily distinguished from each other by the length of the pronotum (the shield covering the abdomen) - the 'slender' species being long and tapering and extending beyond the folded wing tips, and the 'common' species being short with a pronounced central ridge and revealing the wingtips.

As the two images indicate there can be a fair degree of colour variation and texture within the 'slender' species. Whether this is related to sex, maturity or environment, I cannot say. The upper image was of a smooth, two-tone specimen found in long dank grass, whereas the lower image is representative of the specimens I found in more open, bare earth habitats.

Their adult overall body length is no more than 16 - 18mm. This 'slender' species favours damp, marshy environments and the 'common' variety can be found in drier heathland or open woodland places.

Their hopping capacity is quite amazing. The one in the lower image covered 1060mm in one bound - that's 60 times it's own body length! And no doubt it might have been capable of more with some encouragement.


DateSighting
06.06.2004 Seen after rain, in a strawberry patch close to a field margin ditch.
05.05.2005 In long dank, coarse grass, on a Protected Roadside Verge.
17.05.2005 Back garden close to pond.
28.05.2005 On a patch ofwaterlogged ground at Benniworth.
11.04.2007 Several seen by the pond margins at the Horncastle Community Woodland area.



 Female Common Earwig.  Male Common Earwig.

Common Earwig

Forficula auricularia

There are some 1300 different species of earwigs world wide. More than 30 species are found in Europe and of these, four are resident in the UK. As the common name suggests, Forficula auricularia is the most numerous in Europe and at 12mm long is the largest of the UK species. The other three UK species range from 5mm to 8mm in length.

Length apart, the main species identification feature is the shape of the pincers (cerci) at the end of the abdomen. These are subtly different between species. Although they can look quite fearsome they are rarely used aggressively. When threatened they can be raised, scorpion style, in a defensive display but their main function is to clasp partners in the mating embrace.

They are also a gender indicator. The upper image is of a female with gently curved cerci held slightly open in a 'wary' mode. When completely relaxed the pincers would be nearly closed, touching. The lower image is of a male with its much more substantial pincers raised slightly nervously. If it were to be handled roughly, the pincers are capable of giving a nip that might cause one to jump but, are unlikely to break the skin of anyone bar those with the softest, most tender skin.

The female exhibits considerable maternal tendencies. Having laid a clutch of more than 50 eggs in an underground chamber, she will look after them, licking them to keep them free from fungal growth and bringing insect and plant food back to feed the newly hatched young. Having seen the strongest and fittest leave the nest, she is however not averse to devouring the runts of the litter. Perhaps it is an inate method of population control, part of nature's 'survival of the fittest' regime.

Adults feed nocturnally on plant and animal matter and may be found all year round, in all manner of habitats. Rotten wood is a favorite location where they have the choice of the vegetable matter or the small invertebrates that also inhabit it. And I often find them in peanut feeders hung from trees.

They will hibernate through the worst winter weather in crevices, or under stones or tree bark, prior to breeding in the Spring. As the young develop they will shed their skin and may appear creamy white until the new skin hardens off.

The two small flaps between the thorax and the abdomen are elytra, hardened wing cases. Beneath these lie a pair of intricately folded wings, giving the earwig the rarely used opportunity to fly. It has been suggested that the name earwig was derived from these ear shaped wings.



DateSighting
29.01.2009 Female found indoors.
23.07.2009 Male found in the strawberry patch helping to clear up over ripe fruit.


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Mole flea

Mole flea

Hystrichopsylla talpae

When you have seen one flea, you have seen them all - I thought.

This one, at 5mm overall body length, definitely attracted my attention. A mature, well fed specimen, with abdomen fully distended might reach 6mm. Compared to the 2 - 3.5mm length of human, cat, dog and hedgehog fleas this makes it a giant among fleas. It is the largest of the Eurasian fleas.

But, fortunately, this species confines itself to the nests and tunnels of moles, voles, mice, shrews, etc. and equally re-assuring, it is regarded as 'not abundant'.



DateSighting
09.06.2005 Solitary specimen found on the corpse of a mole.




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