Sebacina epigaea for confirmation

[RobSutton]

I found this yesterday growing on bare soil (and party over decaying leaf fragments) under Beech at Malham Tarn. I think it is Sebacina epigaea from looking through Fungi of Switzerland but haven't had a chance to examine it microscopically yet. Are there any other possibilities I should be thinking about?

[fairplay]

Hi Rob,

Well spotted !
I only have the same information as you have (FoS 2), but I would guess the main clincher would be the presence of the "scattered so-called resting spores...." and also the hypobasidia look to have a 'thumb' present whereas its nearest look-a-like, S.incrustans, is 'just 4 fingers' with no 'thumb' if you see what I mean.

What's the betting though that it's nowhere as clear-cut as that when actually looking down the scope !

Neil.

[RobSutton]

Thanks Neil

I've done some microscopy now. The hypobasidia fit generally; divided with four "fingers" and a "thumb" though this seems simply to be the hyphae from which the next basidia will develop and I'm not sure it would be an important distinguishing character.



The spores were a little on the narrow side of things at 10.2-14.7µ x 6.5-8.1µ (FoS gives 10-13u x 8-10µ) and there was no sign of "resting" spores.



So it seems to fit Sebacina but not perhaps epigaea on the spore front. Any one else any thoughts?

[Chris Yeates]

Originally Posted by RobSutton

Thanks Neil

I've done some microscopy now. The hypobasidia fit generally; divided with four "fingers" and a "thumb" though this seems simply to be the hyphae from which the next basidia will develop and I'm not sure it would be an important distinguishing character.



The spores were a little on the narrow side of things at 10.2-14.7µ x 6.5-8.1µ (FoS gives 10-13u x 8-10µ) and there was no sign of "resting" spores.



So it seems to fit Sebacina but not perhaps epigaea on the spore front. Any one else any thoughts?

hi Rob

am I correct in assuming it's not got clamps? there are several Sebacina species keyed out in Nordic Macromycetes Vol. 3; your spores are there or thereabouts for S. epigaea, but I would do a spore-drop and leave that for 24 hours, that should trigger the formation of resting spores if it's going to form them; I also assume you've mounted in congo red?

we are of course not a million miles from: http://www.wildaboutbritain.co.uk/fo...7-post530.html though Exidiopsis does have clamps, and in that species quite different spores

good luck with it all

Chris

[fairplay]

Isn't that a single resting spore showing very faintly at top middle of the first photo (at 10 o'clock to the circular spore) ?
Not very conclusive I know.

Neil.

[Chris Yeates]

Originally Posted by fairplay

Isn't that a single resting spore showing very faintly at top middle of the first photo (at 10 o'clock to the circular spore) ?
Not very conclusive I know.

Neil.

honestly don't think so . . .

Chris

[RobSutton]

Originally Posted by fairplay

Isn't that a single resting spore showing very faintly at top middle of the first photo (at 10 o'clock to the circular spore) ?
Not very conclusive I know.

Neil.

Hi Neil - I had a good long look at all the spores on the first spore drop I did and couldn't see anything apart from regular shaped spores. I've started another off and will leave it for longer to try and see if I can get any resting spores.

Originally Posted by Chris Yeates

hi Rob

am I correct in assuming it's not got clamps? there are several Sebacina species keyed out in Nordic Macromycetes Vol. 3; your spores are there or thereabouts for S. epigaea, but I would do a spore-drop and leave that for 24 hours, that should trigger the formation of resting spores if it's going to form them; I also assume you've mounted in congo red?

we are of course not a million miles from: http://www.wildaboutbritain.co.uk/fo...7-post530.html though Exidiopsis does have clamps, and in that species quite different spores

good luck with it all

Chris

Thanks once again Chris - it was mounted in Congo Red and I could see no clamps. I've started off another spore drop and will see what turns up.

This is another of those occasions when I'm hampered by a lack of literature - specifically in this case Nordic Macromycetes Vol. 3. I can access the Keys from it through MycoKey which came with Funga Nordica. Even though those keys are in Danish I can get a rough translation of them through the wonders of Google Translate which actually does a very passable job of turning Danish mycological terms into English. I can't get hold of the descriptions to go with the key unfortunately- try as I might Volumes 1 and 3 of Nordic Macromycetes seem totally unavailable on the second hand market.

Are there any other sources of more readily available descriptions for these types of species that you know of?

[RobSutton]

After leaving the specimen to release spores for a couple of days I started to find a few odd shaped spores:



Some of them seemed to have irregular rounded lobes, some more pointed protuberances they vaguely seem to match illustrations of Sebacina epigaea resting spores but having never seen them before I'm not sure this is what they really are.

[fairplay]

That 'resting spore' between 7 and 7.5 looks remarkably like the one I tried to point out earlier in the first photo.

Neil.

[RobSutton]

Hi Neil

You're right it does but they still don't really resemble the few illustrations I've seen of these resting spores which all seem to be based on that drawing in Fungi of Switzerland vol 2. It looks like nobody else has really bothered looking at this thing in detail, you can normally find a few micrographs of spores on a website somewhere to compare things against.