Sunday, 26 June 2011

Nearing 1400 species

The Spotted Orchids are now well advanced, with many specimens to be seen in the right places. The first is a good 'clean' Common Spotted Orchid:

Common Spotted Orchid
This second specimen - which was growing very nearby - has features of both Heath Spotted Orchid (the frilly lower lip, with only a hint of a central tooth) and also Northern Marsh Orchid (the dark background colour)
Hybrid Spotted Orchid
As I was examining the orchids, I spotted an Eristalis hoverfly attempting to nectar. I realised I had to work quickly, so I rattled off a few shots, and was rewarded with this fine shot of the hoverfly with the attached pollinia from the orchid:
Eristalis hoverfly with orchid pollinia
The hoverfly has a short tongue, which means it has to force its head deep into the flower to attempt to reach any nectar. Unfortunately for the hoverfly, the nectar is located down a deep tube, and can only be reached by insects with a long tongue, so the attempt is always futile. But the pollinia, which contain the orchid's pollen, are very sticky and attach themselves to the hoverfly's face, causing the hoverfly to withdraw and fly off. It then flies off to another orchid and pollination takes place. I have occasionally seen hoverflies sitting on other plants, trying to remove the pollinia. Score: Orchids 1, Hoverflies 0.



The Willow Leaf Beetle Lochmaea caprea is very common on its host plant where the larvae cause extensive damage to the underside of the leaves:


Willow Leaf Beetle - Lochmaea caprea

The Devil's Coach Horse beetle - Staphylina olens - is one of a large and difficult family of beetles - the Rove Beetles.
Devil's Coach Horse Beetle
All beetles have a pair of wings that fold up inside an outer, hardened pair: the elytra. In the Rove Beetles the elytra are extremely short and the wings are folded several times to fit under their hard casings. I have marked the elytra in the picture above, and it is clear that some severe folding is required to pull the large wings into such a tiny space.

To give some idea of scale, the Willow Leaf Beetle would comfortably fit between the antennae of the Rove Beetle.


The wet early summer has been great for fungal rusts. Pucciniastrum epilobii is a common rust on Willowherbs; in this case Rosebay Willowherb:

Willowherb Rust - Pucciniastrum epilobii
New to me.

It's worth mentioning here that fungal parasites are a good indicator of close relationships between species: Rosebay Willowherb looks quite different from other members of the Epilobium family, but has the same fungal parasite.

Thursday, 23 June 2011

Despite the rain

The weather continues to be very unsettled, but at least the rain does stop for a little while from time to time.

The parasitic ichneumon wasps are becoming very numerous at the moment, which makes sense, because now is the time when their caterpillar hosts are around in large numbers. Ichneumons are extremely difficult to identify to species since the literature is fragmented and it takes microscopic analysis to separate them. This is compounded by the fact that our 3000 or so species converge on a very small number of colour patterns across all families. Very few can be identified by sight, although I can do a couple. Achaius oratorius is one of the larger species at 3 cm. long:

The Ichneumon Achaius oratorius
Another one was kind enough to pose for some close-up shots:

Female Ichneumon wasp
That medium-length ovipositor suggests that this species parasitises larvae which live inside thick-stemmed plants, such as umbellifers.

This next one compounds the colour pattern problem. If you compare it with the sawfly from here, you will see that sawflies and ichneumons also converge on very similar patterns.

Ichneumon wasp

A couple of posts ago, I showed the Banded Snail. This is the very closely related Dark-lipped Banded Snail - Cepaea nemoralis:
Dark-lipped Banded Snail - Cepaea nemoralis
New to the site.

Every clump of Raspberry plants has a few Raspberry Beetles flying around:
Raspberry Beetle - Byturus tomentosus
The grubs of this beetle are the white 'worms' that are frequently found inside the fruit.


The very delicate Lesser Stitchwort is currently in flower, and can be seen climbing through grasses and other flowers, using them for support:

Lesser Stitchwort

Neoascia podagrica is the smallest hoverfly that I have found on the patch. It's never found far from lying water, and this specimen is on an opening flower of Tormentil:
The hoverfly Neoascia podagrica on Tormentil


Micromoths are also very numerous at the moment, with new species appearing daily. This is the very common Celypha lacunana, which feeds on a wide range of plants.

The micromoth Celypha lacunana
Most micromoths feed on a single plant species or sometimes on a family of plants, but Celypha lacunana has a very wide range of foodplants, including Male Fern:
Larva of Celypha lacunana on Male Fern
This flexibility of choice of foodplants is clearly one reason for its success.

I usually associate the micromoth Eupoecilia angustana with later months of the year, but this is an early year, despite the awful weather.

The micromoth Eupoecilia angustana

Lastly, a new micromoth for this site: Incurvarea praelatella. The larvae feed on various members of the Rosaceae family of plants; probably Meadowsweet in this area.
The micromoth Incurvarea praelatella
Other members of the family are leaf-miners.

Tuesday, 14 June 2011

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.

Monday, 13 June 2011

Heath

This heathy area was under coniferous plantation until about 8 years ago, and the original flora and fauna are now slowly returning as the land reverts. Willows, heathers, rushes and mosses are the early colonisers, and these largely dictate which other species can be found.

Despite the awful month of May - during which it rained every day - most species are still a bit early this year, so I thought it was time to catch some Spotted Orchids before they reached full flower, when they are not nearly as attractive as they are in the early flowering stages.

This area has Spotted Orchids that cover the spectrum between Common Spotted Orchid and Heath Spotted Orchid, although the closely-related Northern Marsh Orchid that I showed last week is only about 1 kilometre away. These orchids all hybridise freely, and back-cross, so there cannot be any 'pure' specimens left. I can safely predict where I will find specimens that look most like Heath Spotted Orchid, and those are generally on the very edge of ditches, or even in lying water. I strongly suspect that the form of these hybrids is tightly governed by the micro-climate that they live in, and happily refer to all of these specimens as ecomorphs of hybrid Spotted Orchids. To that end I have started to give them a 'parentage percentage', which specifies how much of each of the parents I think are present in each specimen.

Here are a couple that I would place firmly in the Common Spotted Orchid camp, because the front lobe of the flower has a strong tooth:

Common Spotted Orchid

Common Spotted Orchid
The next pair have the outer sides of the flower more rounded and frilled, which sees some aspects of Heath Spotted Orchid creeping in. The spike is also often flatter:
Spotted Orchid

Spotted Orchid

I have included the next shot because it shows the rotation of the flower, which forms upside down, and then rotates into its upright position as it opens:
Spotted Orchid
I think that's my new favourite orchid photograph. Absolutely lovely.

The next shot shows an oddity that appeared in this location about 5 or 6 years ago:

White Bush Vetch
It's Bush Vetch, but rather than the normal blue/purple, it's purest white. When I first saw it, I suspected that some chemical dumping had taken place, but it has spread over the years and has jumped to an area that used to have the normal blue type. It's not unknown for blue or purple flowers to have white variants, and I'm told that this is more common in the west. Maybe the dampness has something to do with it.

Another few heath species have made returns. The first is Heath Milkwort, with the flower just opening:

Heath Milkwort


And my favourite Speedwell, Heath Speedwell, which forms tall, elegant spikes:

Heath Speedwell

The next two shots show two very closely-related micromoths, each about 5mm. long, and which are both leaf-miners on grasses. The first is Elachista luticomella:
Elachista luticomella
And the gorgeous Elachista argentella:
Elachista argentella

I spotted these ants attending their aphids on Willow:
Ants farming aphid for honeydew

Ants often 'farm' aphids, taking the exuded honeydew back to their nest, and protecting their aphids from attack by other species.

Wednesday, 8 June 2011

False dawn

The high pressure weather system lasted approximately 36 hours, so we're back to rain again.

A few of our day-flying moths are quite butterfly-like in appearance and habit, although the smaller size will generally be a major clue to the difference. This is the Clouded Border -  Lomaspilis marginata -  which is associated with various trees. In this location it will be Willow:

Clouded Border moth  - Lomaspilis marginata

There are quite a few different species of Soldier Beetle in this area. This all-red version (apart from the black knees) is Cantharis pallida:
 Soldier Beetle - Cantharis pallida
Given that we're in early June, I suspect that its close relative Rhagonycha fulva will soon be appearing everywhere, especially on the flowers of various Umbellifers.

This isn't a new fly to me - I see it every year - but it is a new identification. It's the Callophorid fly Lucilia caesar:
Callophorid fly  Lucilia caesar

The Callophorids contain Bluebottles, Greenbottles and Flesh Flies, which are all recyclers of carrion.

Ichneumonids are now around in large numbers. This is perfectly reasonable, since there are many caterpillars and other insect larvae around to parasitise. This one was flying between - and carefully inspecting - the unrolling fronds of Lady Fern, presumably looking for moth or sawfly larvae:
Ichneumonid on unfurling fern frond of Lady Fern

This moth larva might well be one of its targets, although I haven't identified it yet.

Moth larva on Cow Parsley

It was crawling up the stem of Cow Parsley, but it isn't one of the Umbellifer feeders. Perhaps it was just sheltering from the rain.

Friday, 3 June 2011

A dry day!

Today was the first dry day since 28th April, so I wasted no time.

The Orange Tip larva continues to graze on the Cardamine seedpods:

Orange Tip larva on Lady's Smock
The micromoth in the next image is the first of two new species for me on today's page. It's Coleophora albicosta, which feeds on Gorse, spinning up inside the flowers and then, eventually, a seedpod.

The micromoth Coleophora albicosta
I like the configuration that Coleophora specimens have....very elegant.

The 6mm micromoth Elachista apicipunctella is a leaf-miner on a number of grasses:

The micromoth Elachista apicipunctella

Moth Flies, or Owl Midges have the most amazing hairy wings. The drag must be immense for such a small (4-5 mm wingspan) creature:

Owl Midge

I thought this close-up of the Banded Snail Cepaea hortensis was worth showing:
Banded Snail Cepaea hortensis

Because of the incessant rain, I missed the very start of the local orchid season. Some specimens of Northern Marsh Orchid already have open flowers:
Northern Marsh Orchid Dactylorhiza purpurella

With all the wet weather we've had, it's no surprise that the fungal rusts are so prominent. Puccinia urticata is specific to Nettle, and can cause these swellings on leaves and stems:
Nettle rust Puccinia urticata 
Fungi are quite expert at manipulating the shape of plants for their own benefit; in this case to maximise the surface area for spore production and dispersal.

Athous haemorroidalis is one of the Click Beetles. Click Beetles have a mechanism (clearly shown in the picture below) whereby they can trap and release a notch on their pronotum with a sudden click and go flying up in the air to right themselves if they get stuck on their back.


Click Beetle Athous haemorroidalis

An identification that has been bothering me for perhaps 8 years has finally been resolved. The Sawfly below is a male Tenthredo livida, which can be distinguished from other Tenthredo species that have white-banded antennae by the two-tone (pale v-shaped) stigma on the wings. You can just make out the red abdomen which identifies it as a male:

Sawfly Tenthredo livida (male)
As larvae, Tenthredo livida eat a wide range of plants, but the most likely candidate in this location is Raspberry. Now that I know what it is, I can check back on Sawfly larvae that I have previously photographed on Raspberry and check them for a match. I like tying up these connections, even if they take 8 years to resolve.

St. Marks Flies continue to appear through the year, and it's now time for Bibio pomacaeus, which is readily identified by the red legs:

St. Mark's fly Bibio pomonae
(The leaf it's resting on belongs to another Northern Marsh Orchid.)

Flies belonging to the Empidae are sometimes known as Dance Flies because they gather in swarms and move up and down in the air as they fly around each other. This is Empis stercorea, which spends its time between dances by catching other insects and sucking out their body fluids with that long proboscis:

Snipe Fly Empis stercorea

Agromyza nana mines Red Clover leaves, and the single larva can be seen right in the centre of the leaf.
Leaf miner Agromyza nana on Red Clover
I think I have a new favourite picture, but I rather suspect I'll get a new favourite, soon.