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Psathyrella and Panaeolus

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These are very fragile mushrooms. In fact, one criteria for identification is that the mushroom does not survive the trip to bring it to an identifier. Psathyrellas are related to most inky caps, except they do not have the enzyme to turn to ink and the caps are not strongly striate. Both have dry caps, usually attached gills, black (or very dark) spores and they often have white stems. Only occasionally is there a partial veil leaving a ring. They are all saprophytic. There are over a hundred species reported from the PNW but they are little studied and many of them probably do not represent true species. I admit I have a special penchant for Psathyrella, maybe because they are an underdog mushroom that few people seem to care about, but they have a special gracefulness. Cautious experimentation has shown many species of Psathyrella to be edible and delicious, but you need a lot of them to make any kind of quantity. Do not try this yourself as they are difficult to ID correctly to species and there have been no real studies of their safety.

Panaeolus are very difficult to tell apart from Psathyrella, and it is not clear what they are related to. The black spores mature irregularly, making some black and some paler spores on the gills at the same time, giving them a mottled appearance. They are not recommended as food as they mostly grow on dung and could be contaminated. There are also several hallucinogenic species.

The mushrooms in the Psathyrella and Paneolus families have a cellular cap cuticle (the top layer of cells are inflated and round) like Agrocybe and the Bolbitiaceae (and the Russulaceae, but their entire fruitbody has round cellular elements). This sometimes gives them a subtle granular look, but it also makes them susceptible to breaking in any direction, not just radially from the cap to the centre. Put a little bit of pressure on the cap by bending it and see if you can get it to easily break like in the first picture - that might indicate a cellular cap cuticle, although an old rotting mushroom of any kind is also likely to break easily in any direction.

Cellular cap cuticle: an odd way for a cap to split.

Fragile: I tried to keep it in one piece, honest.

Panaeolus mottled gills - from spores that mature irregularly.

Panaeolus is more typically on dung, or if not, has mottled gills and is in grass. Otherwise, see Psathyrella, below.

Psathyrella - usually found on the ground or wood, black or very dark spores, dry caps, attached gills, often white stems and very fragile fruit bodies that are hard to keep in one piece. Pieces of the cap of any shape and size may break off. Those with a partial veil usually leave material hanging off the edge of the cap instead of around the stem like a ring (except for one distinctive species). The hygrophanous caps often start dark and fade to pale tan. Some have recently been split into several new genera, including those with rough spores into the genus Lacrymaria.

Unfortunately, there are many species exceedingly difficult to tell apart and with little to distinguish them, so you will just have to browse them all. First, these are the more delicate species, yet with a long stem. They have larger spores (>10u) than most other Psathyrellas.

P. gracilis grp (semivestita/bifrons/ochracea, etc) - <3.5cm, long stems, graceful and delicate, with the largest spores. Some with veil, some not.

Some call them P. 'corrugis' if they have pink at the top of the gill faces (closest to the edge), and P. 'intermedia' if not.

P. prona is pinkish capped, may or may not be a member of the P. gracilis grp.

P. bipellis (barlae) is a sweet smelling member.

These species have white velar material all over the cap and stem, sometimes making the stem somewhat shaggy when fresh. One even has a ring!

P. longistriata - the species that has a ring on the stem.

P. olympiana - <4cm, on wood, rusty brown fading to tan, cap margin with veil material and wrinkling in age. Stem and cap are white-fibrillose when fresh, as in P. canoceps, but stem is thicker. Has "metuloids" like Inocybe!

P. canoceps - <3.5cm, fibrillose cap and stem, but paler and/or less stocky than P. olympiana. No pleurocystidia, actually a Coprinopsis!

P. caput-medusae - very stocky, very scaly cap and stem. <5cm. Clustered.

These have unusual habitats.

P. candolleana grp - honey coloured, near urban hardwoods, veil material on cap margin, <7cm. No pleurocystidia.

P. typhae - spring, <2cm, grows on leaves and stems near water. Related to P. candolleana.

P. hirta - <2.5cm, cap covered in white removable hairs, found on dung like Panaeolus, resembles P. canoceps but dark brown, fading.

P. carbonicola - on burnt ground, <6cm, chocolate brown fibrillose cap, fading to paler brown.

P. epimyces - grows on rotting Coprinus comatus, <6cm, white

Other miscellaneous Psathyrellas.

P. hydrophila (piluliformis) - clusters on hardwood, <5cm, red-brown fading to tan, veil material on cap, which may wrinkle when dry. (See also P. spadicea and P. longipes). Smallest spores.

P. septentrionalis - very similar.

P. multipedata - strongly clustered, small (<2.5cm), on soil.

P. spadiceogrisea - spring and fall, found in muck, rusty brown fading to tan, <8cm, cap margin with veil material and wrinkling in age. Gregarious but not clustered.

P. circellatipes - similar spring species on or under aspen.

P. longipes/atrofolia - <7cm, veil remnants on cap, more conical than the similar P. hydrophila and P. spadicea.

P. fusca/fuscofolia - Less conical. Rather nondescript.

P. conopilus - <4cm, very conical. Now in Parasola.

P. uliginicola/subagraria - <10cm, large, grey fibrillose cap, under aspen/other trees. Now called Coprinopsis uliginicola. Spores may not be very dark.

P. gruberi - sweet smell, <6cm

P. gossypina (delineata) - <10cm, stocky like P. uliginosa but rusty, wrinkled cap with more veil remnants. Now called Typhrasa.

P. maculata - margin hung with veil material, fleeting ring on stem, hairs on cap become dark and don't come off, <6cm.

P. ammophila - growing in sand. Red brown, fading. <4cm.

P. spadicea - clustered like P. hydrophila, stockier, red-brown spores. No veil material, resembles Entoloma, <6cm. With Inocybe-like metuloids. Now in Homophron.

P. sublateritia - brick red spores

P. aquatica - a Psathyrella that may actually be unique by fruiting under water, found in Oregon's Rogue River.

Species with scales and rough spores have been placed in the genus Lacrymaria. Sometimes sturdy enough to not resemble Psathyrella.

L. lacrymabunda (velutina) - scales on cap and stem, 5-10cm, robust, in waste places.

L. echiniceps - even scalier stem, in forests.

L. rigidipes - scales on cap and stem, <5cm and less robust. Compare Psathyrella olympiana, etc.

L. subcinnamomea - <4cm, also not robust, spring in waste places, cinnamon flesh and scales.

 

Panaeolus - much like Psathyrella, but usually on dung (with one important exception). The gills are mottled dark and light from irregularly maturing spores. Often hygrophanous. My best guess is that they are related to the Bolbitiaceae.

Also consider Psathyrella hirta, which grows on dung without the mottled gills.

Panaeolina foenisecii - dark brown warty spores may put this in its own genus. In grass, dark brown, dark band of colour around cap edge. Hygrophanous, fading. Up to 3cm. Darker stem than Psathyrella with more distant gills.

Panaeolus acuminatus/castaneifolius - smooth, black spores. In grass.

Panaeolus campanulatus grp - in dung, bell shaped, lead colour. Up to 5cm. Veil sometimes leaves material hanging off cap margin.

P. acuminatus - no velar material

P. fimicola/ater - smaller, not bell shaped but flatter caps. <2.5cm. P. ater (if distinct) is blackish.

P. semiovatus - the species with a ring. Stocky, up to 5cm or more. On dung.

P. subbalteatus - dark band of colour around the cap edge. Stocky, <5cm. Not bell shaped as P. campanulatus, similar to P. solidipes if the band has faded. On dung.

P. solidipes (phalaenarum) - stocky, <5cm, like P. subbalteatus, without the dark outer band.

P. alcis - very small on dung. <1cm. Northern species.

P. cyanescens - turns blue from Psilocybin. <4cm. On dung.

 

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