Hairy disco and Tricholoma-like for id

[SheffieldLass]

Two from yesterday that I've drawn a blank on ...

The first, on larch cones:



Spores typically 8.6-10 x 1.5-2.1um, asci 42-50 x 3-5um, paraphyses 66-115x3.7-6um. Stipe not obvious.
Unfortunately the Bioimages website is unavailable at the moment, which I find very useful for finding what grows on certain substrates, and if luck is in, has photos and microphotos. I've found that there are two white hairy discos that grow on larch cones, Hyaloscypha leuconica and Arachnopeziza laricina, but not got any micro information to see whether either fit.


Then this one, under oak and willow. Size about 75mm dia cap, cap is viscid with a peelable skin. Smell, density and robustness rather like St Georges. I've not found any spores, nor any mature basidia (I'm hoping it will mature and produce some). No obvious cheilocystidia, but the basidia are very long ... 84-100 x 6-7.6um. No obvious clamps. Gills are adnexed, flesh is white in cap and stem. The gills and flesh do bruise brownish, very slowly.



I thought Tricholoma or Calocybe but didn't find anything that quite fitted, ruled out Melanoleuca and Leucopaxillus. Any ideas?

Melanie

[mollisia]

Hallo Melanie,

for the discomycete, there is the need of seeing the hairs. Judging from the microfoto, where one paraphyse is to see, You have a Lachnum species. It seems not to be Lachnum virgineum as it is nearly sessile. But for identification more data are needed, as the shape and size of the hairs, the presence or absence of croziers at the ascus base.

Your "Tricholoma" is Russula foetens (or subfoetens) or may be grata. Take a deep breath, whether it smells like rubber or like almonds. To separate foetens from subfoetens (if this is possible at all ...) you need to test the stipe surface with KOH, whether it turns chrome yellow or not.

best regards,
Andreas

[SheffieldLass]

Originally Posted by mollisia

Hallo Melanie,

for the discomycete, there is the need of seeing the hairs. Judging from the microfoto, where one paraphyse is to see, You have a Lachnum species. It seems not to be Lachnum virgineum as it is nearly sessile. But for identification more data are needed, as the shape and size of the hairs, the presence or absence of croziers at the ascus base.

Many thanks Andreas

There do appear to be croziers at the base of the asci. At least I think that is what they are. I've measured a few more of the hairs .. they are very variable in length, from 50-115um long, 2.7-6um at widest point, lance shaped. A few fruitbodies have very short stalks, the majority are nearly sessile.

hairs
crozier

Originally Posted by mollisia

Your "Tricholoma" is Russula foetens (or subfoetens) or may be grata. Take a deep breath, whether it smells like rubber or like almonds. To separate foetens from subfoetens (if this is possible at all ...) you need to test the stipe surface with KOH, whether it turns chrome yellow or not.

best regards,
Andreas

silly me ... I even briefly thought russula, but I just did the 'does it seem brittle' test, and these are quite robust, I guess from the almost enclosed shape as they are young ... ignored the peelable cap, and indeed the cellular nature which were staring me in the face. As for smell, it smells like Trametes, sort of rubber and bitter almonds mixed together!! not unpleasant but quite pervasive. It is funny how when a type of smell is suggested, the brain (or mine at least) seems to then smell that smell. My initial notes were soapy with slightly acidic/fruity/lemony overtones .... so not sure which one fits that! Taste is hot, kicks in after a few seconds. And I've ordered some KOH, should arrive tomorrow .. thought it was about time I got some. These days it seems it is not readily available, but thanks to WAB (one of Posch's posts - thanks Posch!) discovered that it is available from an insect specialist supplier in Norfolk.

Cheers
Melanie

[Chris Yeates]

Originally Posted by SheffieldLass

Many thanks Andreas

There do appear to be croziers at the base of the asci. At least I think that is what they are. I've measured a few more of the hairs .. they are very variable in length, from 50-115um long, 2.7-6um at widest point, lance shaped. A few fruitbodies have very short stalks, the majority are nearly sessile.

hairs
. . .
Melanie

are those definitely hairs, Melanie? they look rather like paraphyses, or is it just me?

best

Chris

[SheffieldLass]

Originally Posted by Chris Yeates

are those definitely hairs, Melanie? they look rather like paraphyses, or is it just me?

best

Chris

I'm on a big learning curve with ascomycetes and it just shows you can't believe everything you read on the internet. I checked out paraphyses and it came up with 'hairs' or 'sterile hairs' , and to me the shape is sort of what I'd expected hairs to be.... I've now checked in 'mushrooms demystified' glossary and it describes them as sterile cells, and it very helpfully shows them on the same (fertile) side as the asci, so I presume they are similar to cystidia. So I guess that means I need to get to see those 'proper' hairs that are on the underside .... How do you get to measure them? I just did a squash, so difficult to tell top from underside .... and even more difficult to do a section of a 1mm dia disc which has dried to 0.5mm ... any tips very welcome ... I've got plenty to practice on (I've a few more cones kept moist and cool in the fridge)

I need to find where the WAB glossary is ... I've not found it yet, it must be hiding ...

Melanie

P.S. Just found it ... didn't scroll down far enough. It could do with being directly under the A-Z ...

[Chris Yeates]

paraphyses are rather like 'packing' between the asci - the lance-like shape and the fact that they clearly protrude above the top of the hymenium is why Andreas suggested Lachnum . . .

rather than do a squash try to cut a section (easiest with a convex scalpel blade and a single fruit-body in a small amount of water on a slide - I tend to drag it away from the main drop of water so just enough to hold it in place)

example of a decent section is this one of Pyrenopeziza revincta :


here you can see the short, subglobose, marginal 'hairs', at top right - note there are no protruding paraphyses here!:


and here similar (but pigmented this time) marginal 'hairs' from a section of Mollisia ligni - I've used these as examples of the benefits of cutting a section - longer hairs would be even easier to make out:



and as examples of paraphyses - these reddish ones are among the asci of a Scutellinia species (they actually give it that reddish orange colour)


and you may well remember these - Peziza megalochondra with its diagnostic golden globules in the paraphyses:


hope that hasn't confused matters

best

Chris

[SheffieldLass]

Thanks Chris, that makes it very clear ... though trying to do a section of a tough 1mm disco is another thing again. It either floated around on the surface tension of the water, or if I managed to pin it down it ended up getting pulverised and the hairs broken. But looking at the whole thing dry under the microscope, and then after a few attempts wet, I managed to isolate one whole hair (well hopefully it wasn't a foreign body instead!). Shape is essentially cylindrical, with a rounded end, some with a slight taper or slight reduction in width just before the end. Size seem to be between 100 and 125um long, width approx 5um.

dry x40
wet x40

I think I'll stick with Peziza, they are at least a sensible size to try to handle ..

cheers
Melanie

Hey, I've just noticed that at last smilies and italics buttons work. Not sure why that has changed all of a sudden ... Until now I had to type in code to make them work, and to be honest couldn't be bothered to do that most of the time. So be prepared, I'll probably be doing inappropriate smilies by mistake and get people even more confused ...

[mollisia]

Hello Mel,

no easy thing to make a section through a stipitate discomycete. I usually don't do such things, Mollisia are sessile ...
You got the hair(s) correct and this is the last character needed to be sure of the genus Lachnum. cylindrical, warty, septate and hyaline hairs together with lanceolate paraphyses are the diagnostic features for Lachnum.
To determine species with Zottos key you need three characters to come to the correct subkey:
1. Do the hairs bear lumps of cristals on the apex (like in Inocybe)?
2. Are the paraphyses and the hairs filled with refractive guttules (drops)?
3. Do the asci have croziers?

In your case the answers are no - no - yes, which leeds to Zottos subkey 5.

In this key you are first asked about the oil content of the spores: many oil drops vs. no or only very few oil drops. The second is the case.
Next is the question regarding hair length. You have quite long haris, 70-110 µm long. Then you are asked about the paraphyses, how much they are protruding over the asci. There are species, where the paraphyses do not protrude out of the hymenium and species where this is the case. In your species the paraphyses where clearly longer then the asci, at least 20 µm judging from the spores that I have seen in the same mount your picture. So this leaves us with only Lachnum virgineum and Lachnum "subvirgineum" nom. prov.. As L. "subvirgineum has somewhat capitate hairs, your species is without doubt Lachnum virgineum. Spore measurements are 6-12 x 1,5-2 µm and without drops, hairs are 90-135 µm long at the side of the apothecium.

Lachnum virgineum is very common on cones, but I have not often seen it with such short stipes. Nevertheless the microscopical details leave no doubt to its identification.

[SheffieldLass]

Thanks Andreas, greatly appreciated. It seems that this site where the Lychnum was found likes to do things a little differently from the norm, so why not Lychnum vigineum with rather short stipes too? I've had Coprinopsis semitalis with thinner episporium than normal, Psathyrella spadiceogrisea with atypical cheilocystidia .... I get some lovely rosy purple capped Hygrocybe psittacina (no yellows, blues, greens on it) though with yellowish stipe. Perhaps there was a Chernobyl spiked downpour in the area, or the Bronze Age people performed too many strange rituals on the site ....

Cheers, Melanie

[Chris Yeates]

Originally Posted by SheffieldLass

Thanks Andreas, greatly appreciated. It seems that this site where the Lychnum was found likes to do things a little differently from the norm, so why not Lychnum vigineum with rather short stipes too? I've had Coprinopsis semitalis with thinner episporium than normal, Psathyrella spadiceogrisea with atypical cheilocystidia .... I get some lovely rosy purple capped Hygrocybe psittacina (no yellows, blues, greens on it) though with yellowish stipe. Perhaps there was a Chernobyl spiked downpour in the area, or the Bronze Age people performed too many strange rituals on the site ....

Cheers, Melanie

dead right Melanie - look even the letters in fungal names transmogrify

lol

C