Sunday, 25 September 2011

High heath

It was surprisingly warm in the hours preceding the predicted storm, so quite a few insects had taken the opportunity to fill up on nectar.

This tiny solitary bee was nectaring alongside an even smaller Empid fly on Common Catsear:
Solitary bee and Empid on Common Catsear

Notice the very thin and upturned ovipositor on this tiny Ichneumonid on Marsh Ragwort:

Ichneumonid on Marsh Ragwort

Quite a few insects are reaching the end of their season and will either die soon or hibernate. This is the hoverfly Helophilus pendulus which has been quite scarce here this year:
Helophilus pendulus on Devilsbit Scabious

And there are still a few Common Carder Bumblebees around:
Bombus pascuorum on Devilsbit Scabious

I've seen a few Small Tortoiseshell butterflies flying around the garden this week. This one nectared on Knapweed for a while and then posed perfectly for its portrait:
Small Tortoiseshell butterfly
Small Tortoiseshells hibernate in sheltered places and then wake in March or April to start off next year's generation.

This is a first for me:
The Stonefly Leuctra fusca
It's Leuctra fusca, a member of the Stonefly family and is known as a Needle Fly for fairly obvious reasons. The nymphs are fully aquatic, but I found this adult hiding on the underside of a Willow leaf which I was examining for the orange fungal rust. The nearest running water is a stream about 50 m. away.

I always check the front lights for moths at night, and I spotted this Lesser Crane Fly. Those legs look almost ridiculously long.
Lesser Cranefly attracted to light

The proposed fungal foray to Ards in about 2 hours' time hasn't quite been called off yet. But it's going to be close.....

Friday, 23 September 2011

Fungal season

Fungi are popping up everywhere, so it's time to get the microscope dusted down, ready for the new season.

The mushrooms that we see are the visible fruit-bodies of the actual fungus, which is usually underground or buried deep inside some substrate, such as wood. The fungus itself will stay in the same place as long as its partner or food source continues to be available: that explains why a particular mushroom can continue to be found in exactly the same location year after year. I'm now beginning to expect my usual crop of Phaeolepiota aurea on the same spot on my lawn at the same time every year. This is a rather scarce mushroom, which is thought to be a nettle associate:

Phaeolepiota aurea
At the beginning, the underside is completely sealed, providing a secure environment for the spores to develop:
Phaeolepiota aurea

Later on, the seal drops to form a ring and the millions of spores are released to be carried by the wind.

Recent studies on Phaeolepiota aurea have confirmed that compounds of cyanide remain in the mushroom, even after cooking, so it has been added to the list of 'poisonous' fungi.

I have previously written about the structure of lichens: fungi which have captured algae in order to utilise the energy that the algae can generate from sunlight. Essentially, lichens cannot survive alone: they need their algal partners to supplement their food supplies. What is particularly interesting, however, is that some fungi can be part-time lichens: most of the time, they survive on their own food resources, but they can capture algae on a temporary basis in order to survive transient periods of hardship. A number of fungi can do this, but it is the Omphalina family which is best known for it.  Omphalinas are small, delicate, trumpet-shaped fungi that are associated with mosses. This specimen is about 8mm. across the cap:

Omphalina griseopallida

I know of a few Omphalina species in my area (we have lots of mossy locations), but this one is new, and looks most like Omphalina griseopallida. I'm taking a spore print to see if that helps with the identification.

Spore prints are one of the basic tools in identification of fungi, and the spores of some species give very strong clues about an identification. This is the spore print of a new species to me: Stropharia aurantiaca.

Spores of Stropharia aurantiaca at x400

Stropharia aurantiaca is a relatively recently-named (1930's) fungus which appears in bark and sawdust that has been used as a top-surface mulch on flowerbeds. In this case it's in a local supermarket car park It has been found numerous times in Northern Ireland, but I can't find any previous records from Ireland.

I'll try to get an in-situ shot later today.

Monday, 19 September 2011

Post hurricane post

The weather continues to be hateful, but I'm guessing that everyone has been in much the same position.

I went up to the boggy area which has many specimens of the late nectar source, Devilsbit Scabious, and found this specimen of the hoverfly Sericomyia silentis. For those of you who know the size of the flowerhead, it will be apparent just how large this hoverfly is.

Sericomyia silentis on Devilsbit Scabious
Devilsbit is a plant that loves damp, acidic soil, in complete contrast with its close relative, Field Scabious, which needs alkaline soil. Interestingly enough, I sometimes find an occasional specimen of Devilsbit Scabious which has the same colouring as the lime lover:

Pink form of Devilsbit Scabious

It's still 100% Devilsbit, though.

Staying with Devilsbit, I found a few rather interesting specimens that were making an extra flowerhead from an existing one:

Devilsbit Scabious with 'extra' flowerheads

Notice the second 'offshot' appearing to the lower left of the central flower. This phenomenon wasn't restricted to one area of the bog: I found multiple specimens spread over perhaps 200 m.

Some specimens of Angelica have survived the storms: these are mostly ones in very sheltered locations. Specimens out in the open have all snapped at ground level. This flowerhead had a number of Ichneumonids still nectaring on it. There are 3 in this shot:

Actually, I just spotted a fourth, right at the bottom of the shot.

This area has quite a few Scots Pines, and I found a few specimens of Suillus flavidus and its bigger brother Slippery Jack, which are always found in association with Pine. I also found the usual swarm of Hebeloma mesophaeum all the way along the edge of the access road:

Hebeloma mesophaeum 
The mosses are Pleurozium schreberi (red veins) and Rhytidiadelphus squarrosus (green 'stars' at 4, 6 and 8 o'clock).

I recently showed a specimen of the leafhopper Cixius nervosus, but I thought this one showed off those wonderful wing veins at their best.

Leafhopper Cixius nervosus
Leaf hoppers - like so many other true bugs - are quite difficult to separate, but the main identification features are visible in this shot.

1) There are 3 'keels' on the thorax.
2) The black dots on the wing edges are larger than those on the inside veins of the wing
3) There is a rather distinct black bar across the front third of the wings.
4) The area between the eyes and the thorax is brownish-yellow.

Let's hope next week's fungal foray isn't rained off.

Monday, 5 September 2011

New Science

Salmonberry - Rubus spectabilis - is a highly invasive member of the Bramble family - originating in western North America - that was originally brought into Northern Ireland as cover for game birds. I saw my first specimens about 5 years ago in a couple of places, but now it's appearing almost anywhere I look in higher locations. The flower is a bright purple, and the berry is a salmon-pink colour (and is incredibly bitter, as I found out to my cost).

I examined a few plants recently and found a couple of leaf-miners:

'Agromyza ideana' on Salmonberry

'Stigmella aurella' on Salmonberry

The first specimen looks very much like Agromyza ideana, which is usually found on Raspberry, and the second looks like Stigmella aurella, which is found on Bramble. The current literature for miners in Ireland and Britain doesn't contain any records of these miners on Salmonberry, so these relationships are both new to science. (The European literature also has no entries for Stigmella aurella on Salmonberry, so that would likely be new to European science). Both mines are well-developed, indicating that these species will be successful in this new host. I'll have to write this up for the appropriate journals once the identifications have been confirmed by the appropriate experts.

Staying with mines, I checked a stand of Bracken where I had previously found my only specimen of the leafmining fly Chirosia histricina and I found it once again:

Chirosia histricina on Bracken

Underside of Chirosia histricina
Given the amount of Bracken that doesn't have this miner, it seems to have very specific microclimate requirements. The literature says 'shady places', and this is under Ash on a north-facing bank, which would certainly qualify as a shady location.

I was actually on a fungus hunt, but I didn't find much of interest in that respect. I did, however, spot a few specimens of the excellent bumblebee-mimicking hoverfly Arctophila superbiens:

Bumblebee-mimicking hoverfly Arctophila superbiens

I had only ever seen this species once before, in a location some 40 km away, so I was delighted to find it on my local patch. Identification is mainly from the very dark wing shade, the all-black legs and the orange hair on the thorax, whilst the abdominal hair is grey.

I coincidentally spotted the bumblebee which the hoverfly is mimicking - Bombus pascuorum - which is still around, but in decreasing numbers as autumn creeps in:

Bombus pascuorum on Devilsbit Scabious
The mimicry is very well-developed here, right down to the grey patches at the base of the wings.

I also liked this shot of the female Cranefly, showing those incredibly long legs:

Female Cranefly

Eyebright is showing all along the centre of paths now:

Eyebright is broken down into a number of species/subspecies. I'm sticking with Eyebright.

A couple of moths came to light on the one night we've had without rain:

Lesser Yellow Underwing

I caught this one at just the right angle to reflect the flash in its eye:
Flounced Rustic