Bioblitz!

Last Saturday saw Bioblitz 2013 in Ireland: 4 locations competed to see which could record the highest number of species in 24 hours. The full story is at http://bioblitz.biodiversityireland.ie/

I was at Colebrook where we recorded 1086 species to top the list. My specialist areas were leaf-miners, micro-fungi and hoverflies, but most of us recorded whatever we saw during the day. I didn't manage to photograph everything I recorded, but this post contains some of the more interesting images.

Since I was 'doing' miners, I headed directly for the main wooded area and immediately found many mines of the weevil Orchestes fagi:

Mine of the weevil Orchestes fagi

A couple of things are worth noting about this miner. First, the leaves of beech trees have only been open for around a week, and the mine has already completed. The larva can only eat fresh leaves (when they are very soft) so no time is wasted when the leaves are unfurling. Second, most of our leaf mines belong to moths or flies, with a few sawflies making up the numbers: there are very few beetles that make mines. Finally, miners that make corridor mines (like the first part of this mine) are severely limited in size by the width of the mine and thickness of the leaf. Species that make blotches (like the final part of this mine) can grow to much larger sizes as larvae, and hence result in larger adults. Having said that, the adult weevil is only 3 mm. long.

Staying with weevils, here are two shots of another weevil: Phyllobus glaucus:

The weevil Phyllobus glaucus

The weevil Phyllobus glaucus

This is a feeder on broadleaf trees, usually near water. Thanks to Malcolm Storey for the id on that one. New to my species list.

While I was near the river, I also recorded a few microfungi on grasses and leaves, although nothing new to me.

I also found this stonefly, which appears to be one of the Perlodidae, but I don't have a key to get it any closer:

Adult Stonefly

Stoneflies are always found close to water, since the larvae are aquatic.

Another very fruitful area was the marshy area further along the river. This was a wonderful environment with dappled sunlight filtering down to an old pond. The fringe was surrounded by Marsh Marigolds:

Marsh Marigolds

And Skunk Cabbage, which is an escape:

Skunk Cabbage

Each of the plants is around 1 m. across.

New to my Species List.

Further in, I found the Green Tortoise Beetle, Cassida viridis:

Green Tortoise Beetle - Cassida viridis

The Cassida family of beetles are paranoid about safety: the larvae carry an 'umbrella' of dead skin and dung to ward off predators, the adults are 'stealth'-shaped in order to avoid casting shadows, and when they are flat to a leaf, present nothing for a predator to grasp.

New to my Species List.

The hoverfly Rhingia campestris has a tongue which folds and unfolds in a zig-zag fashion. When not in use, it stores it in the projection in front of its face:

The hoverfly Rhingia campestris

Solitary mining bees are very busy at the moment, stocking up pollen to feed their larvae. There are many species of Andrena, and this seems to be Andrena haemorrhoa, although it shows similarities to a couple of Andrena species that haven't previously been recorded from Ireland.

Andrena haemorrhoa mining bee

This Empid Fly had captured a specimen of Bibio marci:

Empid with Bibio marci as prey

Bibio sp. are known as St Mark's Flies because they normally emerge around April 28th. They are a month late this year.

Syrphus sp. hoverflies can be difficult to separate without a magnifying glass. This male has hairy eyes, which makes it safe to call it Syrphus torvus:

The hoverfly Syrphus torvus

Under pressure

High pressure, as in sunny weather, brings out all the insects, so things have been quite busy.

The Common Carder Bumblebee - Bombus pascuorum - is the latest of my local bumblebees to establish a nest. Most of the specimens seen around are still queens stocking up their reserves before the workers emerge for the season:

Common Carder Bee on Bush Vetch

Members of the Empid family of flies are commonly called 'Dance Flies' due to their habit of forming mating clouds where individuals bounce vertically within the cloud. They are voracious predators, sucking fluids from their victims with their long proboscis. Sometimes, however, the proboscis is used to reach nectar in flowers:

Empid fly on Creeping Buttercup

Hoverflies are everywhere at the moment, which is good news: they pollinate flowers, trees and crops, so the more we see the better. Eristalis arbustorum can be separated from other Eristalis species by the lack of a dark stripe down the face in association with the swollen rear leg which is conveniently extended in this shot:

Eristalis arbustorum hoverfly

Rhingia campestris is an increasing species which used to be found mainly near farms (the larvae live in dung), but is now found in most habitats:

Rhingia campestris hoverfly

That long 'snout' contains a folded-up tongue which it unfolds to suck nectar that other insects cannot reach.

Leaf-mining species don't wait long after the leaves emerge before laying their eggs: they have to make use of their only food as soon as it's available. This is the very common Phytomyza ranunculi, which mines various members of the Buttercup family:

Phytomyza ranunculi mining Creeping Buttercup

I increased the light intensity on this shot to show the larva more clearly:

Phytomyza ranunculi close-up showing larva in mine

The mines of Phytomyza ranunculi can be separated from those of the much rarer Phytomyza ranunculivora by the pattern of 'frass' (dung droplets), which are joined up ("string of pearls") in P. ranunculi, but are quite separate in P. ranunculivora (Click here for comparison).


Most predators are adept at catching their own food, but some chance upon their next meal whilst simply wandering about. I saw this Lesser Dungfly discovering an already dead fly and after a brief inspection, it wasted no time in tucking in:

Lesser Dungfly with discovered corpse

I previously showed the newly-laid egg of the Orange-Tip butterfly. As expected, the egg has now turned orange and should hatch in the next day or two:

Orange Tip butterfly egg on Cardamine

Good weather encourages moths to emerge and they can often be seen beside lights at night: I keep one light running to see what I can attract. This is Common Marbled Carpet - a very variable moth (and this specimen is quite worn, making identification even more tricky):

Common Marbled Carpet moth

Just to show what we're up against in moth identification, here is a shot of Goldenrod Pug - Eupithecia virgaureata:

Goldenrod Pug moth

Compare that with my previous shot of the same species here. The only features in common are the (faint) elongated wing spots and the tuft of whitish scales behind the thorax. This colour variation has been named as f. nigra for fairly obvious reasons.

Lastly, a shot of the very common Buff Ermine moth. The caterpillars are very common in wooded areas and look like the business end of a stiff yard brush.

Buff Ermine moth

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.

Sudden bounty

We've had a few wet and dull days and then sudden sun and heat. On today's walk I found perhaps a dozen Large Red Damselflies, many of them very recently hatched.

This is a male:

And this, a female:

When damselflies hatch, they have only an overall pale pink pigmentation (they're called 'teneral' at this stage), but the colour soon develops. This female is taking colour from the top down:

A couple of new hoverflies for this year:

Helophilus pendulus:

And Rhingia campestris:

I always wondered why Rhingia campestris has that very pronounced 'snout', but over the years I have taken enough close-ups to find that it has an extremely long tongue which is folded back and forth inside it. That enables it to reach nectar in flowers that other insects can't reach.

This is an Ichneumonid that I frequently see in summer. It's quite large - about 20mm long, excluding antennae - which means it must target one of the larger moth larvae as a host. Something like the Drinker would be about the right size.

Love that shadow.

Sun!

The view East from Leg 2 of the Hedgerow:



This is by far the smallest local hoverfly - Neoascia podagrica. In order to see them, I have to sit on a verge and wait for tiny shimmering dots to hover into view. This specimen was about 5 mm long. For those of you raised on inches, that's about 1/5th of an inch. Check it out on a ruler.


It took a little while to resolve this pair of Cixiids. These are true bugs - related to the much more common leaf hoppers.


Rhingia campestris is a very visible hoverfly with its rosy abdomen clearly seen in flight. The long 'nose' is a sheath for its extremely long, folding tongue. Previously seen only in rural areas (its larvae live in cow dung), this is now being seen in more urban settings, leading to the assumption that more domesticated dung is also being used.


This male Melanostoma scalare was nectaring on Germander Speedwell and Dog Violets:

Sawflies are closely related to bees and wasps. The female's sting is modified into a saw which is used to cut slits in leaves to hold her eggs.

It starts

The fungal season is well underway, and I found a new species for my list on my first little foray of the year. This is the Earth Fan - Thelophora terrestris. It apparently grows in soil, as seen below, but it tends to form tiers in a straightish line, so I think it's on submerged dead wood. The moss is young Pleurozium schreberi.


The Deceiver - Laccaria laccata - is a very common fungus that can be found anywhere from the youngest plantation to the oldest forest. This is its close relative Laccaria proxima. The most obvious difference is the much darker (and more fibrous) stipe, which can just be seen in the shot below. It inhabits mossy and peaty heath, which is exactly where I found it.


The Hoverfly Rhingia campestris has a distinctively large, pointed, snout. I always wondered why until I saw them nectaring in close-up: they have this enormous nectaring tube that folds away for storage. The flower is Devilsbit Scabious.

I also spotted this recently-emerged Angle Shades moth. Newly emerged specimens have the pink and olive markings, slightly older specimens have only shades of orange/rust.


There's a lot going for the next photograph. The Dungfly Scathophaga stercoraria has caught another fly and is consuming it, hidden deep inside the flowerhead of Angelica. I had to use manual focus to get the shot, squeezed through a gap between the framing flowerheads at the front.


I love the newly-formed seeds of the Angelica that act as a platform for the Dungfly.

Sun!

The hottest place in Ireland, today, and it showed: hoverflies and bees of all kinds were on every flowerhead.

This is another of the mining bees from my garden: the beautiful Andrena cineraria.


That shot required knowledge of the behaviour of the bee: they land and very quickly bury their heads in the florets, so all you get is an abdomen shot. But they tend to do a slow 360 degree turn before they fly off. So if you watch where they land and wait for them to complete their rotation you can get the shot as they prepare to take off.

A few butterflies are now making an appearance. So far I've seen Green-veined White, Peacock, Orange Tip and Large White. This Small Tortoiseshell is clearly showing signs of age..they overwinter as adults and have been flying around for a couple of months, now:

The hoverfly Rhingia campestris rears its young on cow dung, but it has lately been seen in urban areas, so perhaps it has migrated to domestic dung.


One of our smallest hoverflies, Syritta pipiens. The inflated thighs appear to be mimicking a minute bee which is now extinct.



And this one's for Aynia....7-spot Ladybird.