''Psathyrella'' is a large

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

of about 400 species, and is similar to the genera '' Coprinellus'', ''

Coprinopsis ''Coprinopsis'' is a genus of mushrooms in the family Psathyrellaceae. ''Coprinopsis'' was split out of the genus ''Coprinus'' based on molecular data. The species ''Coprinopsis cinerea'' (='' Coprinus cinereus'') is a model organism for mushro ...

'', ''

Coprinus ''Coprinus'' is a small genus of mushroom-forming fungi consisting of ''Coprinus comatus''the shaggy ink cap (British) or shaggy mane (American)and several of its close relatives. Until 2001, ''Coprinus'' was a large genus consisting of all ag ...

'' and ''

Panaeolus ''Panaeolus'' is a genus of small, black-spored, saprotrophic agarics. The word ''Panaeolus'' is Greek for "all variegated", alluding to the spotted gills of the mushrooms produced. Characteristics These fungi are mostly dung and grassland sp ...

'', usually with a thin

cap A cap is a flat headgear, usually with a visor. Caps have crowns that fit very close to the head. They made their first appearance as early as 3200 BC. Caps typically have a visor, or no brim at all. They are popular in casual and informal se ...

and white or yellowish white hollow stem. The caps do not self digest as do those of ''Coprinellus'' and ''Coprinopsis''. Some also have brown spores rather than black. These fungi are often drab-colored, difficult to identify, and all members are considered inedible or worthless (for eating) and so they are often overlooked. However they are quite common and can occur at times when there are few other mushrooms to be seen. The first report of a gilled mushroom fruiting underwater is ''

Psathyrella aquatica ''Psathyrella aquatica'' is a species of fungus from Oregon, first described in the journal ''Mycologia'' in 2010. It represents the first ever report of a gilled basidiomycete fruiting underwater. Discovery It was found by Southern Oregon Un ...

''. The genus name ''Psathyrella'' is a diminutive form of ''Psathyra'', derived from the Greek word ψαθυρος, ''psathuros'' 'friable'. The type species of ''Psathyrella'' is ''Psathyrella gracilis'', which is now known as ''Psathyrella corrugis''.

Characteristics

In order to identify the species it may be necessary to take into account the presence and nature of any

veil A veil is an article of clothing or hanging cloth that is intended to cover some part of the head or face, or an object of some significance. Veiling has a long history in European, Asian, and African societies. The practice has been prominent ...

remnants on cap (which may only be visible on very young

fruiting bodies The sporocarp (also known as fruiting body, fruit body or fruitbody) of fungi is a multicellular structure on which spore-producing structures, such as basidia or asci, are borne. The fruitbody is part of the sexual phase of a fungal life cyc ...

), the colour of young fruiting bodies, which is often more vivid than with older ones, whether the cap is

hygrophanous The adjective hygrophanous refers to the color change of mushroom tissue (especially the pileus surface) as it loses or absorbs water, which causes the pileipellis to become more transparent when wet and opaque when dry. When identifying hygroph ...

(it can well be a translucent brown or ochre colour in a humid state but a pure opaque white on drying out), and the spore size and the presence and nature of

cheilocystidia A cystidium (plural cystidia) is a relatively large cell found on the sporocarp of a basidiomycete (for example, on the surface of a mushroom gill), often between clusters of basidia. Since cystidia have highly varied and distinct shapes that ar ...

pleurocystidia A cystidium (plural cystidia) is a relatively large cell found on the sporocarp of a basidiomycete (for example, on the surface of a mushroom gill), often between clusters of basidia. Since cystidia have highly varied and distinct shapes that ar ...

and

caulocystidia A cystidium (plural cystidia) is a relatively large cell found on the sporocarp of a basidiomycete Basidiomycota () is one of two large divisions that, together with the Ascomycota, constitute the subkingdom Dikarya (often referred to as t ...

, distinctive sterile cells on the gill face, gill edge and stipe respectively. All Psathyrella species are unusually fragile, and both the cap and stem break with very little effort. Unlike most agarics, the caps of ''Psathyrella species'' easily break into triangular shaped pieces.

Selected species

''For complete list see'' List of ''Psathyrella'' species * ''

Psathyrella ammophila ''Psathyrella ammophila'' is a species of fungus in the family Psathyrellaceae and is found throughout Europe. Commonly known as the dune brittlestem, this agaric primarily grows on sand dunes near marram grass, feeding saprotrophically on th ...

'' (dune brittlestem) * ''

'' * ''

Psathyrella bipellis ''Psathyrella bipellis'' is a species of mushroom in the family Psathyrellaceae. Taxonomy The species was originally described in 1884 by French mycologist Lucien Quélet, under the name ''Psathyra bipellis''. Alexander H. Smith transferred it ...

'' * '' Psathyrella candolleana'' (pale brittlestem) * ''

Psathyrella corrugis ''Psathyrella corrugis'', is the type species of the basidiomycete fungus genus ''Psathyrella'' and family Psathyrellaceae. Originally described from Europe as ''Agaricus corrugis'', the species is considered non-toxic but lacking in flesh, flavo ...

'' (red edge brittlestem) (type sp., older synonym of ''Psathyrella gracilis'') * ''

Psathyrella piluliformis ''Psathyrella piluliformis'' is a species of agaric fungus in the family Psathyrellaceae. It produces fruit bodies (mushrooms) with broadly convex caps measuring in diameter. The caps are chestnut to reddish brown, the color fading in age and wi ...

'' / ''Psathyrella hydrophila'' (common stump brittlestem)

References

*Marcel Bon : ''The Mushrooms and Toadstools of Britain and North-Western Europe'' (Hodder & Stoughton, 1987).

External links

''The North American species of'' Psathyrella
by Alexander H. Smith, 1972. (Full text of monograph.) {{Taxonbar, from=Q2705558 Psathyrellaceae Inedible fungi Agaricales genera Taxa named by Elias Magnus Fries