Observation 91275: Agrocybe pediades group

When: 2012-03-25

Collection location: Oakland Hills, California, USA [Click for map]

Who: Peter G Werner (pgwerner)

Specimen available

This collection is Observation 90947, collected by Debbie Viess. Page created to upload micrographs. Original at http://mushroomobserver.org/90947.


Cheilocystidia and spores. DIC, 20X/0.75 NA objective.
Copyright © 2012 Debbie Viess (amanitarita)
Copyright © 2012 Debbie Viess (amanitarita)
Copyright © 2012 Debbie Viess (amanitarita)
Copyright © 2012 Debbie Viess (amanitarita)
Copyright © 2012 Debbie Viess (amanitarita)
Dark, purple-brown spore print.
Pileipellis a trichoderm(?) Brightfield, Congo red stain, 20X/0.75 NA objective.
Pileipellis a trichoderm(?) Brightfield, Congo red stain, 60X/1.40 NA objective.
Cheilocystidia. DIC, 60X/1.40 NA objective.
Cheilocystidia and spores. DIC, 60X/1.40 NA objective.
Spores and basidioles. DIC, 60X/1.40 NA objective.

Proposed Names

54% (3)
Recognized by sight: Just a guess bases on the overall appearance. Those Agrocybes – not exactly perfectionists. the bottom 3 slides…, how was this done? What does DIC stand for?
91% (2)
Eye3 Eyes3
Based on microscopic features: Seems to be the only thing with this combination of characteristics

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

Eye3 = Observer’s choice
Eyes3 = Current consensus


Add Comment
More micrographs of this species
By: Peter G Werner (pgwerner)
2012-03-30 14:11:17 CST (-0500)


The pileipellis hyphae in the Eurpean collections look a bit broader and closer to the more “cellular” type typical of Agrocybe, but then ours could certainly differ from the European variety in a number of ways.

(Had not seen the AMB Muggia forum before. Very cool!)

I spoke too soon…
By: Peter G Werner (pgwerner)
2012-03-30 13:40:00 CST (-0500)

Reading up on Agrocybe, there are dark spored ones, which of course is quite different from the ubiquitous Agrocybe praecox that so many of us in this part of California are used to. Based on Michael Kuo’s description and photos (http://www.mushroomexpert.com/agrocybe_pediades.html), I’m going with Noah and Gerhard’s ID of Agrocybe pediades. I didn’t think this collection looked like photos I’ve seen of that species, but the specimens are older than most of what is shown in available photos. The micro characters fit, and the pileus surface darkens in KOH.

Pileipellis in Agrocybe
By: Gerhard Koller (Gerhard)
2012-03-30 13:34:22 CST (-0500)

is as a rule hymeniderm or with pear-shaped cells, but not always clearly visible and especially when older collapsed or relatively thin, especially within the pediades group. Cited E. Ludwig’s Pilzkompendium.
I would not rule out this looking at the photo. But who am I to say regarding LBM’s?

By: Peter G Werner (pgwerner)
2012-03-30 13:24:25 CST (-0500)

Yes, absolutely get why you couldn’t place it; neither can I, just based on looking at it. My only other guess was some oddball section of Pholiota with dark spores; have to pour through Hesler and Smith on that one. Agrocybe doesn’t fit well either, as that typically has lighter spores and hymeniform pileipellis.

Martin – DIC = differential interference contrast.

Thanks, Peter.
By: Debbie Viess (amanitarita)
2012-03-30 13:08:24 CST (-0500)

Well, THAT’S clear as mud!!! ;)

Yah, do you get why I couldn’t just stick this one into Agrocybe???!

Nor Stropharia, for that matter…

Fruiting just in time for April Fools Day?
By: Peter G Werner (pgwerner)
2012-03-30 12:57:44 CST (-0500)

OK, so we’ve got a dark purple-brown spore print, and large psilocyboid/stropharioid spores, Galerina-like “bowling pin” type (non-chryso-) cystidia, a trichoderm-type pileipellis (unless I’m misidentifying the pileipellis type) very unlike most Strophariaceae, and a fruiting body with the overall look of Agrocybe or Leratiomyces.

What kind of weird chimera is this! I can’t even place this to genus. I’ll have to start going over literature.

Sorry for the lack of a scale bar. The calibration is kaput on the microscope imaging software I was using, but I also took images of a high-quality stage micrometer under the exact same objectives as I took the micrographs, and a large series of spore photos for measuring purposes, hence, I’ll be able to provide measurements and spores statistics in a few days. I can say that the larger spores in the image are definitely quite large, in excess of 10 micrometers.

Created: 2012-03-30 12:40:50 CST (-0500)
Last modified: 2012-03-31 02:03:06 CST (-0500)
Viewed: 167 times, last viewed: 2017-07-04 03:59:32 CDT (-0400)
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