Observation 10597: Gymnopus luxurians (Peck) Murrill

When: 2008-09-02

Collection location: Madison Heights, Pasadena, California, USA [Click for map]

Who: Jason Hollinger (jason)

Specimen available

grouping of several medium-sized mushrooms, in sunny lawn, no distinctive odor
ST: grayish to cream tomentose, streaked, solid, fibrous, not brittle, a few white rhizomorphs at base
CAP: dry, smooth, shiny, rich medium reddish brown, cuticle a cutis with weakly encrusted brown interwoven but mostly parallel hyphae, encrustation not clearing in KOH, thicker clear interwoven hyphae below cuticle
GILLS: creamy, thick, distant, sinuate, no cystidia on edge, abundant cystidia on face (rounded-mace-like balls protruding just above basidia, very constricted neck), trama parallel
VEIL: no signs of any whatsoever
SPORE: print presumably white or cream, elliptical-oblong, minutely textured?, clear, simple, nonamyloid

I tried really hard to diagnose this via microscopic characteristics of cuticle and lamellae, but predictably failed. It looks like a Collybia (e.g. C. luxurians?), but it clearly has no cheilocystidia and does have pleurocystidia. The key in “How to ID to Genus, Vol III” points me to Tricholoma, but every photo I’ve seen of that genus shows much bulkier/fleshier fungi. I’m afraid the samples were a bit past their prime even before they spent several days in the fridge awaiting my (dis)pleasure.

Help? Please?…


Pleurocystidia, mounted in water, at 400×.
Spores, stained in Lugol’s, at 1000×.

Proposed Names

55% (1)
Recognized by sight
61% (2)
Used references: Used the page Nathan suggested. Assuming spore print is not pinkish (big if), it keys convincingly to this, and matches the description well.
21% (2)
Recognized by sight
28% (1)
Recognized by sight

Please login to propose your own names and vote on existing names.

Eye3 = Observer’s choice
Eyes3 = Current consensus


Add Comment
Thanks for the help everyone
By: Jason Hollinger (jason)
2010-08-21 17:41:09 CDT (-0400)

If I ever manage to find my specimen again, I’ll attempt to confirm or re-diagnose the cystidia, spore shape, etc. Until then, I’ve returned this to “unknown” status. Too bad I’ve never seen another fruiting of this thing, even though I know exactly where to look for it…

Spores not collybioid
By: Joel Horman (jlHorman)
2010-08-21 15:39:31 CDT (-0400)

Collybia (Gymnopus)has lacrymoid (tear drop shaped) spores, which these evidently are not, although the macro-resemblance to C. luxurians is close. Gills should be close to crowded, and the stipe striate and twisted. Since the spores are non-amyloid, and apparently also not dextrinoid, this cannot be Rhodocollybia either. For detailed information see http://www.nybg.org/bsci/res/col/
Good luck.

Why no copyright?
By: Administrator (admin)
2008-10-15 23:56:12 CDT (-0400)

I noticed that the copyright holder for these images is empty. Any particular reason or is this some sort of bug?

By: Alan Rockefeller (Alan Rockefeller)
2008-10-15 00:19:12 CDT (-0400)

Its really rare to have pleurocystidia and no cheilocystidia. You might want to take another look at the gill edges.

Gymnopus is the new Collybia
By: Nathan Wilson (nathan)
2008-09-10 14:46:41 CDT (-0400)

Collybia has been restricted to the group of small species that grow on the old sporocarps of other species (like Collybia tuberosa, the type species for Collybia). Most of the species that we used to think of as Collybia are now in Gymnopus. Roy Halling has a great site on Collybia s.l. which should help.

By: Jim Tunney (Jim Tunney)
2008-09-09 22:28:11 CDT (-0400)

Looks like C. luxurians.

By: Douglas Smith (douglas)
2008-09-07 21:26:44 CDT (-0400)

With the redish stains in the stipe and gills, and the serated edges, try Rhodocollybia.

Are you sure about the pleuro- but no cheilo- cystidia?

Created: 2008-09-07 19:24:36 CDT (-0400)
Last modified: 2014-06-12 20:37:03 CDT (-0400)
Viewed: 109 times, last viewed: 2017-10-06 22:10:31 CDT (-0400)
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