Tuesday, 14 October 2014

Dry weather continues

I postponed my proposed trip to Ards since the dry weather continued and there wasn't much sign of fungal activity. But the 'lure of the west' called me and since I had also agreed to make a radio piece about foraying, the trip eventually went ahead.

As I have mentioned before, Ards peninsula is a rocky outcrop jutting into the Atlantic, so it is a unique environment with ancient forest inland, surrounded by sea, dunes and grassland at its boundaries. This wide range of habitats in such close proximity leads to a biodiversity which never ceases to produce something new on every trip.

As expected, the overall number of fungal bodies was very low, but there was still the usual great variety of species.

We decided to start the trip with a walk around part of the coastal boundary to see what grassland species we could find, and found Hygrocybe pratensis - the field waxcap - in the usual places, but little else of a fungal nature.

Several specimens of this snail were found:

Helicella itala

Keying it out was fairly straightforward: Low spire>large umbilicus>no keel>no lip. It is described as a dune species, so that seems fine.

New to my Species List.

We also found many specimens of the very handsome caterpillar of the Fox Moth:

Larva of Fox Moth - Macrothylacia rubi
Fox Moth larvae are being found in huge numbers all over Ireland this year, and I rather suspect that the very warm summer we had last year is at least partly the reason.

One further grassland fungus was found. This is Clavulinopsis fusiformis, identified by the acute tips to the fruitbodies: 

Clavulinopsis fusiformis
Surprisingly, new to my Species List.

We passed the location where I found Thyme Broomrape a few years ago, but none was seen. Not to be outdone, however, as we reached the boundary of the forest, I saw this specimen in the undergrowth:

Ivy Broomrape
It was surrounded by many plant species, so it was quite impossible to determine its host, and it is beyond recognition from the flowers. Based purely on the surrounding vegetation I will make a stab at Common Broomrape and will have to visit it again next summer when the flowers will be fresh. No Thyme was found nearby (and the habitat was wrong).

Update: our local botany recorder has just informed me that this is a known location for Ivy Broomrape.

Back inside the forest, we found the Blackening Waxcap, Hygrocybe nigricans, doing what it does best: going black.

The Blackening Waxcap, Hygrocybe nigricans
A grass verge had quite a few species, including Helvella crispa and the closely-related Helvella lacunosa:

Helvella lacunosa
We found a few fresh specimens of the Tawny Funnel Cap, Lepista inversa:

Tawny Funnel Cap, Lepista inversa
Other species found: Destroying Angel (again), Birch Polypore, Beechwood Sickener, Chanterelle, and two specimens of what I'm sure was the Miller (which is edible and delicious), but couldn't trust myself to take home due to its similarity to Clitocybe dealbata (which is deadly poisonous).



Friday, 26 September 2014

Catching up

Our unexpected spell of dry weather has continued, and has most certainly delayed the usual glut of fungi that would normally appear at this time of year. Last week, during the practical photography session on a macro course, we encountered dozens of mushrooms that were completely dried up, with the spores lying underneath them on the ground:

Dried fungi with spores underneath and on the cap

Spores are usually wind-borne, but these have simply dropped down onto the grass due to the complete calm. The actual fungi shouldn't suffer, since they are deeply buried inside wood or soil, and persist for years, but there will be little reproduction this year. Note that the caps are also covered in spores. Most spores are produced by the gills underneath, but some species are also able to produce spores via the upper surface of the cap and that looks to be what has happened here.

During a school trip this week, one of the pupils brought me a dead branch with fruitbodies of Chlorociboria aeruginascens

Chlorociboria aeruginascens on dead Oak
This fungus lives on dead Oak and Beech, and isn't too rare, but the fruitbodies seem to appear very rarely; this is the first time I have photographed them. Individual fruitbodies are around 3 - 5 mm. across the cap.

Now that I have the literature on spiders and harvestmen, I'm looking at them much more closely. This is the harvestman Leiobunum blackwalli:

Leiobunum blackwalli (female)

Leiobunum blackwalli (female)
Harvestmen don't make webs, but sit on or under leaves waiting for some prey to walk past. I love the way the white-lined eyes are up on stalks (called a 'turret').

New to my Species List.
  
In 2007 I found a gall on Oak which puzzled me:


Individual galls are secured by flaps of tissue on veins of the leaf, but are able to detach and fall to the ground. It didn't appear in references, and I couldn't get a name for it despite hours of searching. The new edition of Redfern and Shirley says it's very common, but I hadn't seen it before, and I haven't seen it since. It's made by the Cynipid wasp Neuroterus anthracinus

New to my Species List.

Most leaf miners stick to a very small set of plants, sometimes just one species, but some are a little more flexible and use a number of plants. This can make identifications tricky, since their appearance can be quite different on different hosts. I struggled a little with this mine of Agromyza idaeiana, which I often find on Raspberry or Meadowsweet, but this specimen was on Bramble:

The leaf miner Agromyza idaeiana on Bramble
The blotch at the end of the mine is much wider than I usually see, since it isn't constrained between veins like it is on the other plants.

Thursday, 11 September 2014

Sun!

This week has been a bit of a surprise: mist in the early morning followed by absolutely clear blue skies all day. Quite delightful, really.

I have been examining my local Hawthorns for miners and came up with this rather interesting specimen:

Stigmella perpygmaeella mine on Hawthorn

It's the mine of the micromoth Stigmella perpygmaeella, which is new to my species list. At point A (the head of the mine) we can see the miner (yellow larva with oval head). But at point B we can see another, different, larva. This second larva has the look of a hymenopteran about it (round shoulders, tapering body) so it will be either a sawfly larva or a wasp larva of some sort. It is clearly heading towards the miner, so it looks like we have a predatory larva in the mine. I knew that miners could be parasitised by Braconid or Chalcid wasps, but this is an entirely new relationship. More research....

While I was working the Hawthorn, I found a few nymphs of the Hawthorn Shieldbug:

Final instar nymph of Hawthorn Shieldbug
This is the fifth and final stage of the nymph: at the next metamorphosis it will be the adult.

Capitalising on the good light, I went up to the local heath to see what I could find. Devils-bit Scabious is one of the latest plants to flower, and the path was lined in purple.

First to catch my eye was this pale pink variant:

Pink Devils-bit Scabious
I have seen this sport before, but it seemed there more around than usual this year. It looks like the pale colour doesn't put off the pollinators.

This shot shows another oddity which I see from time to time:

Viviparous flower of Devils-bit Scabious
The bud at the top is a viviparous flower growing out of the flower below it. It isn't a branch, because the stem arises from inside the lower flower. Not quite sure why this happens.

Here's a shot of the hoverfly Episyrphus balteatus on a normal flower:

Episyrphus balteatus on Devils-bit Scabious
I noticed this cluster of Russulas from the path side and immediately thought "Russula mairei", which is common everywhere around here, but then I realised there were no Beeches around:

Russula emetica - The Sickener
The trees above are Fir and Pine and the mushrooms are growing through Sphagnum. This is classic habitat for Russula emetica, which I have been hunting for perhaps 10 years. This habitat is perfect for it, so I wonder why it has taken so long to get here. New to my species list, at last.

Russula emetica - The Sickener
Russula mairei is known as the Beechwood Sickener, but Russula emetica is known as The Sickener, as you might guess from its specific name.

Friday, 29 August 2014

Pollinators

This week I was giving a talk as part of an international conference about pollinators. If you mention pollinators most people immediately think of bees, and bees are certainly extremely important plant pollinators. Other groups of insects, however, are also important in the pollination process, and I was covering hoverflies. I spoke to the other speakers on non-bee pollination (one discussing beetles, another covering butterflies and moths and a third talking about ants), and it was clear that there is actually very little scientific literature out there that discusses and compares the contributions made by these other groups.

I made the case that since there are more species of hoverfly than bee in Ireland, and there are clearly more hoverfly specimens than bee specimens, that hoverflies are obviously an important player in plant reproduction. Yes, bees are 'busier', visiting more plants per minute than a hoverfly, but bees also take pollen back to their nests to feed their young. This takes pollen OUT of the plant reproduction process, rather than assisting. Further, there are bees that short-circuit the nectar-taking process by cutting into the rear of flowers, thereby bypassing the pollen-gathering part of the arrangement. This is theft.

I then went on to discuss the lifecycle of hoverflies, and pointed out that some species of hoverfly lay their eggs in bee nests. Their larvae eat the detritus in the nests, keeping them healthier and more productive. So hoverflies are assisting some bees. Lastly, I discussed the fact that some hoverfly larvae feed exclusively on aphids: yet another beneficial aspect to this group.

The beetle and ant speakers struggled to find any evidence of plant pollination other than incidental or accidental transfers as they moved from plant to plant. The one saving grace as far as ants are concerned is that they 'farm' aphids, thereby providing a food source for the hoverfly larvae!

After the talk we went on a tour around the excellent conference site (Oxford Island at Lough Neagh) and I took the camera with me.

The following shots show how things are progressing with the new 70D camera.

This is the original shot (reduced in size!) of the hoverfly Eristalis pertinax:

Eristalis pertinax - original full-frame shot

This is the same image cropped to show the whole insect:

Original image cropped to the insect 

And this is a crop to just the wing veins:

Crop showing just the wing veins
These three images were all taken from the same original. This camera continues to astound me with its performance.

The image is also instructive in another way: In the field I initially identified this as Eristalis pertinax. But when I blew it up on the computer I noticed the dark wing shade and the yellow margins to the abdominal tergites. The only species on my patch that looks like that is Eristalis horticola, so I changed my identification without any further thought.

I showed the images around and was informed that this was indeed Eristalis pertinax, and that occasionally it can have a dark wing shade! Lesson learned: although I can safely identify my local set of species, I need to take into account variations that might occur outside my immediate geographical area.

Someone found this mine on Wood Avens and brought it for me to look at:

Mine of Stigmella aurella on Geum
I immediately recognised this as a Stigmella mine (central frass in a corridor mine), but didn't know which species of Stigmella mines Geum. So I took the images and went back to the office to check the internet. Turns out it's the very common Stigmella aurella, which I have often shown on Bramble. Bramble and Geum are both members of the Rosaceae, so they're quite closely related. It's nice to get confirmation from details like this that the plant taxonomists were right!

Finally, I found a few pristine specimens of the Parasol Mushroom, Lepiota procera:

Lepiota procera - Parasol Mushroom
I think I'll have a fungal foray to Ards on Sunday.

Tuesday, 19 August 2014

Different eyes

Last week I returned to my old stamping grounds in Berkshire, England, as part of a 1750 mile round trip through Scotland, England, Wales and Ireland. It's 15 years since I lived there and I was astonished at how much had changed. Then I suddenly realised that it was me that had changed most of all: I instinctively knew that I was on alkaline soil (something I never knew before) and there was even evidence of chalk. This kind of information just wasn't apparent to me before I began to study wildlife seriously.

The plants, of course, are different to those that I find on my home acidic soil, and that leads to a completely different set of leaf-miners, since most miners are specific to a single plant or family of plants. Different plants, different insects, a 15 year gap. Everything seemed new and different.

One of the first 'new' species I saw was the leaf-mining micromoth Cameraria ohridella on Horse Chestnut:

Mines of the micromoth Cameraria ohridella on Horse Chestnut
This species has spread rapidly northwards and westwards since it arrived in the UK around 2001, and it has now been found in Belfast and Dublin. Described as new to science in 1986, it affects mainly Horse Chestnut, but can also be found in Acer species. Although the leaf damage is extensive, affected trees are not under threat, since the mines are started after the leaves have established.

The Harlequin Ladybird, however, is a serious problem: 
The Harlequin Ladybird, Harmonia axyridis 
This is larger than our native species and out-competes them when they have a common food, such as aphids. When Harmonia arrives, the local species are all but eradicated. I saw plenty of these, but no native 7-spots, 10-spots or 14-spots.

Another interesting observation: at home I have Red Campion and Red dead-nettle. Here I found White Campion:

White Campion

And White dead-nettle:

White Dead-nettle
Coincidence?

There was also evidence of garden escapes, with some Geranium species in large swathes. I found this gall on many of the leaves:

Uromyces geranii on Geranium sp.
It seems to be the fungal rust Uromyces geranii.

All of the above species are new to my species list.

I managed to sneak up on a resting Painted Lady. These are always rather tricky to photograph:

Painted Lady butterfly

Quite pleased with that picture.

I also managed to get a shot of a male Common Blue Damsel:

Common Blue Damsel
These were particularly frisky on the day.

I still have some species that I need to identify, so I'll post more as information arrives.

Thursday, 24 July 2014

Little finds

Some of the best finds can be unexpected and completely accidental.

En-route to pick up a car earlier in the week there was a detour, so I stopped at a lay-by to confer with Mr. Google. I spotted this wonderful little moth out of the car window and jumped out with the camera. It's the Latticed Heath:

Latticed Heath Moth
This is a Clover feeder and is found in grassy areas. One generation in this area.

New to my species list.

Yesterday I was called out to examine what appears to be a fungal rust on Himalayan Balsam:

Fungal attack on Himalayan Balsam
This is an extremely invasive plant, and it has now reached most parts of Britain and Ireland. To date the local populations have been free from predators or parasites, since it is an introduced alien. But last year I found a leaf-miner and now we have this fungal rust, so perhaps we can expect populations to begin to weaken. That might just open up opportunities for other parasites to take hold, so perhaps we're seeing the start of some kind of weakening/control. I can certainly confirm that the miner has spread very rapidly and has now been found in perhaps half a dozen new sites around the country, some hundreds of kilometres apart.

After I had examined the rust, I went back to the car-park to find a stand of Comfrey on a stream-bank. Some of the leaves had a fungal attack and I have now identified this as Melampsorella symphyti:


The fungal rust Melampsorella symphyti on Comfrey
There are very few records of this on the FRDBI and seems it's new to Ireland.

A few more recent images are instructive:

This is the excellent Nettle associate Calocoris stysi: 

The Mirid Bug Calocoris stysi
The leaf-mining fly Pegomyia solennis is one of the few that are communal. Always found on Rumex sp., especially Broad-leaved Dock:

Larvae of the communal Dock miner Pegomyia solennis
Some leafhoppers are absolutely minute. This is the Meadowsweet specialist Eupteryx signatipennis, about 3 mm. long:
Meadowsweet specialist leafhopper Eupteryx signatipennis
New to my species list.

Finally, another oddity. I have a huge Lavatera bush in my garden and it is usually covered in bees, wasps and hoverflies all nectaring. I had assumed that the bees were gathering pollen, too, but it seems that the pollen is no use to Honeybees and Bumblebees: they actively remove it after they have taken the nectar:

Honeybee removing pollen from Lavatera.
Note the empty pollen baskets.

Wednesday, 16 July 2014

Background research

Weather hasn't been too good recently, so I have been working away researching all manner of creatures from spiders to beetles, to parasitoids.

A colleague in Galway found a parasitised larva of the 4-spotted Footman moth a couple of weeks ago. Here is her original image:



The larvae of the parasitoid have consumed non-essential parts of the moth larva and have emerged and pupated en-masse. The original larva is still alive, and will move away from the batch of parasitoid cocoons. There are a number of strategies that parasitoids use to avoid being parasitised themselves, and allowing the original host to temporarily survive and walk away will lessen the chances of the parasitoid cocoons being detected by the hyperparasitoid, since the hyperparasitoid will use the original larva as a vector and be distracted by it.

I received the cocoons last week and yesterday two adult Braconid wasps emerged. The remaining 22 cocoons are still intact.

I used the key to Braconidae to get the specimens to genus (Apanteles), and then used a 1973 paper from the Bulletin of Entomology to refine the search (there are over 250 species of Apanteles on the UK list). The most striking photographic evidence for identification are the wing-veins. 

This is my photograph of the diagnostic part of the wing veins of the Galway specimen:



And this is the reference image of the wing veins (rotated to be in a similar position to the sample above):



The similarity is striking, and leads us to Apanteles octonarius, which is known to be a parasitoid of the 4-spotted Footman moth. The adult parasitoid wasp is 2.5 mm long.

There is one previous record of Apanteles octonarius on the Irish list, and that was from Mayo in 1911. I am now seeking validation of this identification, since this group is new to me (apart from Apanteles glomeratus, which parasitises the Large White butterfly, and which I showed last year.)

Another bit of research centred around the Tachinid Eriothrix rufomaculata. This Tachinid can be readily identified by the two red marks on the top of the abdomen, (and which give it its specific name):


I predicted last week that this fly would shortly appear, since I had noticed a large number of other migrant species, including the Red Admiral butterfly, the hoverfly Scaeva pyrastri and a number of migrant moths. I am certain that this fly is migrant to this country, since I can predict its arrival by monitoring the arrival of other species.

That photograph was taken using the new 70D, which continues to amaze me daily.