Mycena Identification help needed

[RobSutton]

Found this on the trunk of a Beech tree growing in moss. Cap was 6mm in diameter on the largest specimen.



Spores 8.0-9.5µ x 5.2-6.3µ with a Q value of 1.4-1.6:


Cheilocystidia were covered in wart like outgrowths and some had very long finger like outgrowths:




Hyphae in the outer layers of the stem had tiny outgrowths:


I keyed it out using several sources to Mycena mirata but then checked the basidia and found them to be four spored whereas all my sources suggest M.mirata only has two spored basidia, this was constant in several specimens from the same location:


The only other possibilities I could get to in Funga Nordica were M.arcangeliana and I think my specimens were too small and with too long diverticulae and the stem was the wrong colour; and M.filopes or M.metata which are mostly two spored with some four spored basidia but would seem to be terrestrial on plant fragments rather than on mosssy tree trunks.

Does anyone have any idea on this one - a job for Mycena Man I think

Thanks, as always, for any suggestions.

[flaxton]

Rob
You have done a good job with trying to give all the necessary information. A view of the gills showing the number and attachment would be good and was there a recognisable smell?

The fruit-body and location has the look of Hiemalis but the Cheilocystidia rule that out.

Another possibility is M erubescens a species that bleeds a milky liquid and your photo shows some signs of this on the stipe. Unfortunately the spores and basidia rule that one out

Mirata is the right shape, the right location, the cheilocystidia is OK, the spores good, the stem hyphae good, the number of lamellae not sure but the only fly in the ointment is the basidia.(Could you loose that picture) I know some species (galericulata) start the year with two spored basidia and end with four but I have no note of mirata being a species that does this.

Mirata is by far the best fit I can see so unless there's a Mycena man out there with a better suggestion I would go for that.

Mal

[Ken Burgess]

I would have arrived at Mycena mirata with the information supplied, although the 4-spored basidia would have been a puzzle.

Interestingly, in his online Mycena key, Aronsen says:

"In the literature M. mirata is only described as 2-spored, and all my own collections have been 2-spored. A collection made by M. Krikorev, Sweden, however, proved to have 4-spored basidia."

Perhaps the species is not sufficiently well studied?

Ken

[RobSutton]

Many thanks Mal and Ken - I think it will have to go down as Mycena possibly mirata. I might try and find a few more to see if any have two spored basidia, there seem to be quite a few similar looking ones on trees in the area.

[Alantb]

Hi Rob;
Maas Geesteranus says 2-spored but also sometimes 1-spored and from these basidia he finds spores at 15 microns yet!. In my experience, also, the cystidial projections are from 2 to 7 microns, longer for instance than on M. metata or filopes. Your excellent picture of the cystidia would seem to indicate this.
Maas also says 'no pleurocystidia' - if you find any more I suppose you could check this, it would be interesting to know as an additional feature.

Lovely pics by the way, what's your setup?
Regards, Alan

[RobSutton]

Thanks for the extra information Alan, the four spored basidia are still a bit of a puzzle; unfortunately I've not had a chance to try and have a look at any more specimens of this species. I didn't find any pleurocystidia when I examined the first one.

The photos are from a ScopeTek DCM200 cctv camera attached to a Brunel SP100 Microscope. I've just checked their website and they don't seem to feature this particular model of camera anymore!

All the best.