When: 2008-07-29

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

Who: Jason Hollinger (jason)

No specimen available

GEN: small mushroom, dense cluster at edge of lawn where it was recently dug up (substrate probably lawn not manure)
ST: 50 × 4 mm, hollow, fragile but fibrous, whitish, covered with white particles or scurfy, encrusted at top with tiny clear granules when viewed at 400x
CAP: 2-3 cm wide, pale brown, smooth, viscid, minutely striate, conical, cuticle cellular with tightly-packed spherical cells (~20 µ)
VEIL: partial veil forming white skirtlike movable ring, all have slipped down to near base, whitish and smooth on both sides
GILL: adnate, mottled brown, dusting of brown spores clearly visible at 30x, white scurfy margin on gill edges, tissue wavy-filamentous, no pleurocystidia, cheilocystidia small bowling-pin shaped ca. 7.5-9.0 µ wide at tip
SPORE: print some kind of brown, oblong but somewhat irregular or bent, subtle apical pore, brown, smooth, 7-9 × 4-4.5 µ

Note, I never saw fresh material, so I never got a spore print. Looks “chocolate brown” or “deep brown” on face of gill, but don’t trust me.

I used the trial key in Conocybe in Pacific Northwest. Mine matches the description of “Conocybe filaris” (now Pholiotina rugosa, apparently) in the key pretty well, but it doesn’t match the photographs of fresh fruiting bodies I see on MO or Mykoweb or elsewhere. There is no orange component in the cap in the dried material, and the stem is clearly uncolored. Both characters are distinctly unlike the photos I see. However, the description in the key above calls the stipe “ivory”, making me wonder about these pictures… But maybe I’m just confused.


These are at least two days old. However, there was one tiny one still in semi-fresh condition buried under the grass. One stipe still shows the movable ring clearly.
Spores at 1000x, in water, marks are in µ.
Cheilocystidia, at 1000x, in water, marks are in µ.
Cuticle, at 1000x, in water, marks are µ.

Proposed Names

-25% (3)
Based on microscopic features: See notes.

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

= Observer’s choice
= Current consensus


Add Comment
Careful of the pleurocystidia
By: Douglas Smith (douglas)
2008-07-31 06:26:14 AEST (+1000)

With the few Psathyrella I’ve look at, and I keep promising myself to get back to the others sitting on the shelf, a lot of the cystidia can look like big basidia, and that makes it hard to be sure about pleurocystidia, is it another basidia or a cystidia? You should try to see where on the gill in the edge and the cheilocystidia is, then crush the mount to separate the cells, and look again, to see if you see cystidia in among the crushed gill face. You should do this anyway, to get a better photo of the cheilocystidia than what is shown here.

But the real difference between the two genera will be the spores are “brown” instead of “black”, although a few Psathyrella are brown-black… But the other thing to look for is that the pileipellis is an epithelium in Psathyrella and a hymeniform in Pholitotina. Which means the cap is cellular in both, so just looking down on the surface they look the same. But in the hymeniform is cellular in one layer, like the basidia in the hymenium, and the epithelium will be cellular in multiple layers. If the sample is dried, it is easier to get a thin radial section of the cap, and then this should be observable. The key is thin, if too thick it can look like mulitple layers, where is just many cells thick, they get a bit squashed together. You can try to get a thin section, and only look at the ends, where the razor is leaving the shroom at an angle, and section gets thin.

It looks like Pholiotina arrhenii starts with a white stipe when young, but then it mentions that is turns brown from the base at it ages. I saw a photo of P. arrhenii on the web, and it is not that uncommon a species, it is just no one is going through the microscopic effort in CA to look for it. But the photos seem to suggest a fairly brownish stipe, with a yellow-brown cap.

no pleurocystidia
By: Jason Hollinger (jason)
2008-07-31 04:21:59 AEST (+1000)

… at least none that I could find. That seems to rule out Psathyrella longistriata. Seems Conocybe and Psathyrella are in different families, surely there’s some definitive microscopic discriminant, no??

Note the new photo. Upon closer observation, I found one little guy that hadn’t withered, showing the pale brown smooth slimy conical striate-grooved cap. Also the habit is actually one enormous cluster, they are not gregarious as I thought. And the stipes are covered with particles or scurf which apparently wore off in my hand before arriving home yesterday. The substrate is still unclear: proximally they are growing in a dense half-rotten clump of lawn (straw maybe?), but the mycelium could still be in any of a number of substrates.

Try Psathyrella longistriata
By: Douglas Smith (douglas)
2008-07-30 16:33:06 AEST (+1000)

I’m not sure about the Pholiotina. Mostly because you say the stipe is whitish, and in Pholiotina the stipe is usually tan, yellowish, orange-brown, brown. Also the cap should be brown with yellow to orange tones. The spores you show there are fairly dark, more a chocolate or coffee color. I’ve found the Pholiotina spores to be a medium to light brown in the scope. And usually the germ pore is pretty clear.

Look up the description of Psathyrella longistriata in Smith’s Psathyrella monograph. With the off-white stipe, and the darker brown cap, and the dark chocolate brown spores, that might be closer. Also take a look at the cap surface in very thin cross section, the Pholiotina should have the cellular surface in a single layer, and the Psathyrella in multiple layers of cells.

Just an idea…