Brittlestems and many of the Inkcap mushrooms belong to this family.
The size range of fungi in this family is tremendous. For example Coprinopsis atramentaria, the Common Inkcap, sometimes attains a height of 20cm while many of the tiny members of the family are barely 3cm tall. Most are delicate and easily damaged.
Within this group are a few fungi of open grassland as well as many more that are found in dark woodland, either growing on the forest floor or on dead branches or stumps of trees that have been felled.
Not all of the inkcaps belong to the family Psathyrellaceae; as a result of DNA analysis the Shaggy Inkcap, Coprinus comatus, is now accepted as belonging to the Agaricaceae. Many of the inkcaps within the Psathyrellaceae have thin, striate cap margins, narrowly adnate gills and no distinctive smell, but not all of them deliquesce (a decay process whereby the gill and cap material turns into a black inky fluid); however, the Common Inkcap certainly does, as indeed does the Shaggy Inkcap despite being genetically well separated from the other species that carry the 'inkcap' title.
Note: inkcap is sometimes written as ink-cap or ink cap, and in the USA the terms inky cap or inky-cap are used.
Psathyrella fungi, commonly referred to as the 'brittlestems', have narrowly adnate gills with pale edges, no particularly distinctive smell, and stems that become hollow at maturity; their caps and stems are very brittle.
For more information about fungi in the family Psathyrellaceae and a deeper insight into the ecology and structure of species featured in our Psathyrellaceae Gallery pages, please see Pat O'Reilly's latest book Fascinated by Fungi, author-signed copies of which are available online here...