Are these spores amyloid?

[SheffieldLass]

I have a little fungus which is giving me the runaround. No pics of the fungus - someone else picked it. A white one (cap and gills that is), with hyaline spores. I put a bit of the gill in melzers to see whether the gill trama was dextrinoid, which it is. But the spores went, well, the colour you can see. Would you call them amyloid?

Gill trama in Melzer's showing cheilocystidia
Hyaline spores in Melzer's.

Thanks
Melanie

[flaxton]

Melanie
Small white(ish) with those shaped cystidia looks like Mycena flavoalba If it is if you try it again in water you might be able to find some of the cystidia have an amorphous blob at the end.
Back to the original question I would say there has been a definite reaction to the Meltzers (which would be wrong for that Mycena).

Mal

[SheffieldLass]

Thanks Mal. The following will explain why I asked .....

This particular fungus looked like a very typical Marasmius, the M rotula type that is, (although it had a pseudocollarium not a collarium, I think). But the cheilocystidia ruled out M rotula straight away. It had a hymeniderm cap so that ruled out the Marasmiellus genus. Mycetinus genus has hymeniderm cap, but no iodine reactions, and all in Funga Nordica have brownish caps anyway, so easy to rule out that genus. Some former Marasmius have ended up in Gymnopus, but Gymnopus are all cutis/ixocutis or interwoven sort of trichoderm cap, not hymeniderm, so that genus is ruled out. Which I think leaves Marasmius, but I may have missed something?

Anyway I was plodding through the Marasmius key, and it got to a bit where it split on whether the gill trama was dextrinoid. So I got out the Melzers, and the bit of gill on my slide went darkish as it flowed over, so I thought, yeh, iodine reaction. Looked down the microscope and thought red-brown gill trama, yes, dextrinoid, and spores are amyloid. Only there were only two with dextrinoid reactions and only one (Marasmius setosus) where the spore size came close, and the cheilocystidia look something like (although that is usually associated with beech, and there was none of that there, but there was birch and oak, which it can occasionally be found on) ... only then I realised that none of Marasmius are supposed to have J+ spores anyway .... So I'm probably developing a bald patch after all the subsequent head scratching.

Hence my post to see whether others interpret the spores as J+.

Hmmm ... Hemimycena .... right shaped spores, but they're not J+ either ....

So any ideas on genus, please for a Marasmioid fungus, growing on leaf/herbaceous litter, J+ .... Trouble is, when others pick it they often don't tell you what it was with.

And the cap of the little thing shrivelled up and got so miniscule after my manipulations of it that I've lost it on my desk ... and the stalk broke off as I tried to extracate it from the dead litter, which I then lost, so couldn't look for hairs ...

Melanie

[flaxton]

How many lamellae?

[SheffieldLass]

Originally Posted by flaxton

How many lamellae?

Good question ... oh for a photo, but I'm pretty sure it was in excess of the 5-7 for Marasmius setosus. Off the top of my head I'd say it was between 9 and 16, probably around the 12 mark. Also basidia seemed to be 2 spored - I only saw 3 but they were all 2 spored. Spores (8.3)8.9-10.9(12.3) x (3.3)3.9-4.9(5.4)um Qav 2.3.

These are the cells of the pileipellis .. clavate to globose but also cylindrical ones. Those were also in melzers. Well a bit of the cap joined the gill when I did it I think the cylindrical ones were more dense near the cap edge.


Melanie