High Heath

The Green-veined White butterfly has two generations per year. Unusually, the two generations are quite close, with some slight degree of overlap. Summer generation specimens are more strongly marked, with the black markings being darker and sharper than those of the spring generation.

 This pristine specimen is a female:

Female Green-veined White, summer generation

Given the lateness of the year, this is a rather early specimen for the second generation.

I have found the same, strange, earliness in the bumblebees this year. Queens emerged rather late, and nests were subsequently late, with workers not appearing until a few weeks ago. There is usually quite a delay until the new queens and males are ejected, but I have been seeing new queens and males for a couple of weeks now: much earlier than usual. It seems that some species are actually accelerating this year, despite the slow start, and are now ahead of normal schedule, rather than maintaining the 'lateness'.

Male bumblebees are ejected from the nest to fend for themselves, mainly because they do no work and would be an overhead on the nest. They are quite easy to identify, both in behaviour and appearance: they tend to crawl slowly over flowerheads in contrast with the workers which gather pollen almost frantically. They are also rounder, more colourful and have longer hair, giving them a 'fuzzy' appearance:

Male Bumblebee on Common Catsear

Any bumblebee with yellow hair on its face is likely to be a male, although not all males show this feature:

Male Bumblebee showing yellow hairs on the face

It isn't possible to identify these males to species without internal examination, but given the location, I'd go for Bombus lucorum s-s.

The hoverfly Helophilus pendulus is very numerous at the moment, with sightings on every excursion and location.

The hoverfly Helophilus pendulus

But I still examine every specimen, since I know that the much more local Helophilus hybridus can occasionally be found:

The hoverfly Helophilus hybridus

These rarely fly more than a few hundred metres from the boggy areas that contain Bulrush - the foodplant of their larvae. Identification relies on the differences between the markings on the abdomen. I might see only one or two of these each year.

The hoverfly Platycheirus scutatus was split into 4 species quite recently. Irish specimens appear to be the original Platycheirus scutatus s-s.

Platycheirus scutatus, female

Platycheirus scutatus, female

The larvae of these feed on aphids on low-growing vegetation.

Digger wasps can often be mistaken for hoverflies due to the oval yellow markings on the abdomen, the large head and the apparently short antennae: all features of hoverflies. These are predators on hoverflies, killing them and taking them back to the nest to feed their larvae:

Ectemnius continuus

Their appearance enables them to mix with hoverflies and approach them without disturbing them: I have often seen hoverflies and Ectemnius wasps feeding on the same flowerheads.

Hoverflies mimic the colour patterns of wasps and bees with greater or lesser accuracy. This enables them to inherit the protection that the colour patterns give to bees and wasps: birds know to avoid yellow and black -  nature's danger signal. So Ectemnius wasps are imitating hoverflies that are imitating wasps.

Staying with mimicry, Volucella bombylans is a hoverfly that mimics bumblebees (and lays its eggs in bumblebee nests):

The bumblebee-mimicking hoverfly Volucella bombylans

Volucella bombylans comes in at least three colour versions, each mimicking different bumblebees. I would dearly like to know if the different versions choose appropriate bumblebee hosts to rear their young.

Sawflies are very difficult to identify to species without a specimen, a microscope and a key. I have recently obtained a copy of the (55 year-old!) key and have identified this specimen as Tenthredo mesomelas:

The sawfly Tenthredo mesomelas

In an effort to understand these adults and larvae, I am participating in an online effort to gather together images of both adults and larvae of all sawfly species together for the first time.

When I was down taking photographs of orchids (see here), this micromoth flew over my head and landed on the Luzula upside-down, as so often happens.

The micromoth Glyphipterix thrassonella

The larvae of Glyphipterix thrassonella feed on Juncus rushes, which were in profusion. This is the first time I have seen this species since 2005.

Meadowsweet must be a very nutritious plant: there are many miners, micromoths and fungi which use it as a host. This is the fungal rust Triphragmium ulmariae, which is specific to Meadowsweet:

Triphragmium ulmariae on Meadowsweet

Note that the fungus has distorted the stem of the plant in order to maximise its surface area and therefore increase its chance of spore-dispersal.

And this is the mine of  Agromyza filipendulae on the same plant:

Unusually-shaped mine of Agromyza filipendulae on Meadowsweet

Note that this particular mine is atypical: it should have continued spreading to the left, but for some reason it has turned back at the fourth vein. Perhaps it was parasitised.

Making hay

Two posts in two days!

The first two shots show the larval case of the micromoth Coleophora serratella on Alder. 

The larva cuts out part of the leaf and rolls it up into a cigar shape, changing the case a couple of times as it grows. The cutouts can be seen at the lower edge of the leaf, with the case towards the top of the leaf:

Larval case of micromoth Coleophora serratella

The larva moves slowly over the surface, grazing as it grows and eventually pupates, still inside the case.

Coleophora serratella on Alder

This is really just a form of leaf-mining, but it allows the moth to grow larger than it could if it was constricted to living inside the tight confines of the leaf. There are quite a few different Coleophora species, each mining different groups of plants from trees through shrubs to clovers. The clover one is particularly well-hidden as it uses one of the flowers as a case and then hides amongst the other flowers. I have looked in vain for those, but maybe they're too well-hidden.

Marsh Cinquefoil has to be one of our most easily-recognisable flowers, although I think it's rather scarce: I have only ever found it in two locations. There are a few specimens between the edge of a bog and a stream which runs along the hedgerow at this point:

Marsh Cinquefoil

The hoverfly Rhingia campestris has an extremely long tongue (arrowed) which enables it to reach nectar that other insects cannot reach.

The hoverfly Rhingia campestris on Raspberry

The tongue is so long that it needs to be folded up for storage when not in use, which leads to the very unusual 'snout' that can clearly be seen in this shot:

Rhingia campestris, showing 'snout' for storing the tongue

Rhingia campestris is a hoverfly that has been increasing its range in the past few years. It used be seen relatively close to farms, and the larvae are known to live in cattle dung, but the hoverfly can now be found far from agricultural areas. Perhaps it has started to use other sources of food.

There are many leaf miners active at the moment, and I spotted this very common leaf-mining fly Agromyza filipendulae on Meadowsweet:

Leafmining fly Agromyza filipendulae on Meadowsweet

This particular mine was worth showing for several reasons.

1) Notice that the frass (dung) is laid in two parallel lines, along each side of the mine. Many of the leaf mining flies have a very simple scraper to excavate the leaf interior and this only works in a vertical plane. But the leaf is thin and arranged horizontally, so the miner has to lie on its side as it mines. Between each slice, it flips its body through 180 degrees and that points its rear end towards the other side of the mine, leading to two parallel tracks of frass. Other miners (e.g. moths) have more sophisticated chewing mandibles and can mine in one position, leading to a single line of frass down the centre of the mine. The two-track/single-track configuration is one major feature in the identification of leaf miners.

2) The mine has changed at the point arrowed: the frass becomes confused and the larva has changed from green to a dark colour, so I'm pretty sure the larva has been parasitised at the point marked. I rather suspect we're going to find an Ichneumonid emerging instead of a fly.

3) There is a minute (1-2mm) Owl Midge at the lower right hand corner of the picture.

Of all the species that I study and photograph, I continue to find moths the most difficult to identify: the variation within species can be staggering and the similarity between different species compounds this. And that's not counting in the variation due to wear and tear. You need to learn the crucial separating features to be sure: merely looking at pictures won't always help.

The Mottled Beauty can be identified from other Beauty species by the curved black crescent at the end of the black cross-line, marked below:

Mottled Beauty moth

Mottled Beauty is a true polyphage, feeding on many trees, shrubs and flowers.

If at first you don't succeed...

The Lissonota sp. ichneumonids have started to lay their eggs in unsuspecting moth larvae hidden inside grass seedheads. I've been following these for a week, now, and yesterday I was rewarded with a couple of shots of the egg-laying taking place:

Notice the antennae being used to pinpoint (ouch!) the location of the larva.


This shot shows the ovipositor at the moment it was being retracted. It's finer than a human hair.


This shot appears to be of a male (of a completely different species):

Staying with parasitic insects, these two Tachinids were on adjacent Bramble leaves. It looks as if they were pointedly ignoring each other. I see a great many Tachinids, and this shows just how many larvae of moths and butterflies are parasitised each year.

Some leaf-miners are very easily identified as such. This is Agromyza filipendulae, on Meadowsweet.


But the mines of Phyllonorycter species can easily be overlooked. This is Phyllonorycter rajella, on Alder. The pupa is only 2mm long, so the adult moth will never be recognised as such in flight.


That's the year half over, and it was only just new year.

A right mixture

Another new moth: Beautiful Carpet - Mesoleuca albicillata. This is 'widespread, but not numerous'. Wingspan about 20mm.


After a brilliant start to June, it has been very wet for the last two weeks. Today we got a bit of sunshine and I saw this tattered Speckled Wood basking in the sunlight:

Suddenly it was dive-bombed by another that chased it off and then occupied the same basking spot. This one is in better condition, but I think it's a little early for second generation specimens.

I think that the best colour on our hedgerows is provided by the flower-buds of Greater Birds-foot Trefoil:


The red more-or-less dissappears when the flowers are mature. This flowerhead was juxtaposed with what looks like Melanoleuca melaleuca:

To finish off: The Meadowsweet leaf-miner - Agromyza filipendulae. It has had to backtrack when it inadvertently bumped into its old track. (The mine starts in the purple centre portion, then goes clockwise until it gets trapped above the purple portion, when it resumes its clockwise track onto a new portion of leaf. Exit hole is bottom left.)