Peziza sp.?

[NickWood]

Hi Forum,

Hopefully you can help to identify this fungus. From my reading, it may be a Peziza sp. The lack of a significant stem seems to rule out a Helvella sp.

Only one, found last week in low grass and moss on a canal bank, a few metres away from the hedgerow on the opposite side of the towpath. No trees near.

Cap 4cm, darkish to light brown; the stem not much more than a stub 7mm x 7mm (not hollow). Flesh and underside lighter brown, the underside smooth (not wrinkled), with no sign of hairs. Quite a pungent mushroom smell.

I didn’t do very well getting spores, but the few I got correspond roughly in size and features to those in the ascus (ascus: approx. 18.70 μm wide; spores: ellipsoid, minutely warted, 17.91-21.18 x 9.61-12.04 μm). Insets in image of ascus (100x EDF composite) to show spore features.

Attached is an image of the fungus in situ.

I appreciate there are problems adding multiple images, so I’ll attach further images in “Replies”.

Cheers… Nick

[NickWood]

Peziza sp.? Further images:

[Chris Yeates]

Hi

a section through the fruitbody can furnish useful information. There is a helpful basic key here: http://www.fieldmycology.net/GBCHKLST/key.asp?KeyID=8” class=”bbcode_url”>http://www.fieldmycology.net/GBCHKLST/key.asp?KeyID=8

best wishes

Chris

[mollisia]

Hello,

this is most likely Disciotis venosa.

If you have a microscope at hand, you can pick a small piece of the hymenium and squash it in Melzers Reagens (or Luglos solution) -> if the ascus tips turn blue it is a Peziza species. If the ascus tips do not turn blue, it is not a Peziza species, but A Disciotis, a Helv ella, an Otidea, etc. p.p.

My guess is nevertheless Disciotis venosa. If you have it still in fresh condition: It smells like chlorine.

best regards,

Andreas

[Chris Yeates]

mollisia wrote:

Hello,

this is most likely Disciotis venosa.

If you have a microscope at hand, you can pick a small piece of the hymenium and squash it in Melzers Reagens (or Luglos solution) -> if the ascus tips turn blue it is a Peziza species. If the ascus tips do not turn blue, it is not a Peziza species, but A Disciotis, a Helv ella, an Otidea, etc. p.p.

My guess is nevertheless Disciotis venosa. If you have it still in fresh condition: It smells like chlorine.

best regards,

Andreas

Hi Andreas

Yes I wondered about that – it’s the right time of the year. But Nick said the spores were “minutely warted” and the Disciotis venosa apothecia I have seen have always been more wrinkled than that. But I bow to your greater experience, clearly the test you suggest will sort it out.

LG

Chris

[mollisia]

Hello,

I don’t think that the spores on the pictures are warted. I think it is dirt or small bubbles which are laying partly on the spores. The distribution of the “warts” is too unequal to be a real ornamentation.

The wrinkles in Disciotis are due to age – younger fruitbodies are not wrinkled at all, and the wrinkles develop by time.

[attachment=0]Disciotis_venosa_Jena_G1.jpg[/attachment]
young fruitbody of Disciotis venosa

But of course it is only my suggestion and has to be verified by microscopy.

best regards,

Andreas

[NickWood]

Many thanks, Chris and Andreas, for your insights – greatly appreciated!

Unfortunately, a few days ago the specimen had dried to a crisp so was thrown out. I’ll visit the site again this weekend with the hope another has emerged. Perhaps I can then do the tests suggested.

I wonder about the habitat. Isn’t Disciotis venosa associated with woodland? The site I found the specimen would perhaps be best described as grassland.

When I suggested “minutely warted”, I was basing this on the spores in the ascus, and the insets seem to indicate a minutely lumpy rather than smooth surface. (I included the insets as the EDF process I used tends to smooth surfaces).

I’ve attached one more image. I’m not sure this will be more helpful. Top left is one of the free-floating spores I photographed. Below this are two examples of several “green” spores I found (one ellipsoid, one globular) that I took for contamination. On the right is another shot of an ascus.

Many thanks, again, for your help and very informative responses.

Nick

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