Sunday, 10 February 2019

On second thoughts, maybe I won't start getting into Mollisia

These mushrooms caught my eye the other week, growing on a decaying branch of a tree by the stream at Woods Mill.

They looked oysterling-ish. But darker than the ones I usually see.

The fruit body I collected has been sat on my radiator for a couple of weeks, and I finally got around to taking a look at it today.

Masses of spores floated off my little slice of gill, mounted in ammonia.

Spores (in ammonia). 400x magnification.
My measurements of the spores came out at 8.5-10 x 5-5.5 μm{based on 10 spores}.

Having been all round the houses (and through the ID books) with this one, I'm now thinking it's probably an old Peeling Oysterling Crepidotus mollis? Although it doesn't look much like the young C. mollis I've recorded before at Woods Mill. Over on the British Mycological Society Facebook Page, Richard Shotbolt has suggested it could be Crepidotus calolepsis (considered by some authors to be a variety of C. mollis) which is differentiated by its covering of minute rusty-brown scales. Hmm.

Growing with these mushrooms, in the sheltered cracks of the dead branch, I caught a glimpse of something else. Some tiny little grey discs.

I collected a few of these yesterday. Here they are under the stereomicroscope.

I remembered a conversation with Brian Douglas about a small grey disc fungus, which he described as 'mollisioid'. I wondered if what I have here might be a Mollisia species of some kind.

My next step was to Google 'Mollisia key', which brings up a discussion on entitled, "Mollisia - is it impossible?", which makes interesting reading, if you're considering venturing into this dark corner of mycology. The answer's kind of, "Yes, but don't let that stop you having a go."

I don't think I will be able to mount a serious identification attempt on this, as I don't have any Lugols Iodine (and after seeing this article by Hans Otto Baral on 'Iodine reaction in Ascomycetes: why is Lugol's solution superior to Melzer's reagent?', I figured it wasn't worth trying with Melzers instead). But I thought I'd have a little play anyway. See what I could see.

Clockwise from left: Apothecia under the stereomicroscope; apothecia in cross-section, 100x magnification; spore (with small oil droplets?), 1000x magnification; asci and paraphyses, 400x magnification. All mounted in water.

I can say confidently this is definitely an ascomycete, with those spores lined up in long sacs (asci).

It's got pretty long thin spores: 10-13.5 x 3-3.5 μm. And I'm thinking the contents of the paraphyses are slightly refractive.

That's all I got. Hopefully I'm right on it being a Mollisia!

For the record
Date: 09/02/2019
Location: Woods Mill
Grid reference: TQ21761367

Saturday, 9 February 2019

Storm Erik brings a surprise

I stopped by Woods Mill this lunchtime, after Storm Erik had passed through, and came upon a scene of devastation.

An old willow by the dipping pond had blown over and taken out a section of the new dipping platform. I couldn't resist going in for a closer look at this wet woody mess.

Halfway up the trunk, in an area where the surface of the trunk had started to rot, I noticed some little brown clusters growing on old knots of wood.

I'd never seen anything quite like this before, so popped back later that afternoon with a penknife and a collecting box, to get a specimen.

Under the stereomicroscope, I could see that the clusters were made up of tiny round cup-shaped fruit bodies: pale on the inside, tobacco-brown on the outside. I thought they must be an ascomycete of some kind.

With some difficulty, as the individual fruit bodies were so small, I managed to get a thin section of one of the cups under the microscope.

Cross-section through cup. Mounted in water 100x magnification.

The cups are super-hairy on the outside!

Looking more closely, the brown hairs appear to become more translucent (hyaline) towards the tips.

Hairs. Mounted in water 400x magnification.

And I'm thinking they perhaps look slightly encrusted? Not completely smooth anyway.

Hairs. Mounted in water 1000x magnification.
Once I'd got a good look at the hairs, I started looking for asci – the long thin bags full of spores which are a characteristic feature of ascomycetes  on the inside of the cup... but, er, couldn't find any.

I got confused.

But then a vague memory of a cyphelloid fungus flashed across my mind. It didn't take long to track down what I was remembering: a photo on a wikipedia page that I was reading a few weeks ago, after I found that weird cyphelloid fungus on Ulva Island.

This photo in fact:

The clustered Merismodes fasciculata, USA. This image was created by user damonbrunette ©2009 at Mushroom Observer, a source for mycological images. CC BY-SA 3.0, via Wikimedia Commons.
Reckon I'm onto a decent lead here...

The very clustered growth of my collection would be right for Crowded Cuplet Merismodes fasciculata (= confusa). But a quick search on the internet suggests that M. anomala can look pretty much the same. [Malcolm Storey has images of both M. fasciculata and M. anomala on his BioImages website, if you want to see what I mean.]

I see that some folks from the Chinese Academy of Sciences have published a simple key to Cyphellopsis (= Merismodes), in a paper on 'Two new species of cyphelloid fungi (Basidiomycota) from China'. This suggests spore size is a key feature when separating these two species.

I managed to find a few spores, by sitting my specimen upside-down on a glass slide for a while.

Two spores (top left and bottom right). Mounted in water at 400x magnification.
My measurements came out at 8-10 x 4.5-5 μm {based on measurements of 11 spores}. This is close to the quoted measurements for M. anomala (8-11 × 5-6.5 μm) in the paper I mentioned above; and I note that, like mine, Malcolm Storey's collection also came out a bit smaller on the width (8-9/4.5µm).

I think this is pointing towards my collection being Merismodes anomala.

For the record
Date: 09/02/2019
Location: Dipping pond, Woods Mill
Grid reference: TQ21781369