Psathyrella


Psathyrella is a large genus of about 400 species, and is similar to the genera Coprinellus, Coprinopsis, Coprinus and Panaeolus, usually with a thin cap 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 and so they are oft 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.
The genus name Psathyrella is a diminutive form of Psathyra, derived from the Greek word meaning "friable", psathuros. 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 remnants on cap, the colour of young fruiting bodies, which is often more vivid than with older ones, whether the cap is hygrophanous, and the spore size and the presence and nature of cheilocystidia, pleurocystidia and caulocystidia, 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