The Coprinaceae were historically a family of inky-cap mushrooms characterised by deliquescent gills, thin, fragile fruitbodies, and dark spore prints. Caps are typically conical to bell-shaped, often with mica-like granules, scales, or radial striations. Gills begin pale but rapidly turn grey to black, dissolving into an inky fluid that aids spore dispersal. Species are saprobic, growing on rich soil, dung, wood, compost, lawns, and disturbed ground, often appearing in troops or clusters after rain.

Modern taxonomy places most former members into Psathyrellaceae (e.g., Coprinellus, Coprinopsis, Parasola) and a few into Agaricaceae, but the morphological concept of “inky caps” remains a useful field grouping.

The Coprinus genus, in its modern restricted form, contains only a few large, shaggy inky caps, most notably Coprinus comatus. Species have elongate, cylindrical to bell‑shaped caps covered in shaggy, upturned scales, with a movable ring on the stipe. Gills are free, crowded, and deliquesce into a black inky fluid at maturity. Flesh is white, soft, and fragile. These mushrooms are saprobic, appearing in lawns, roadsides, parks, gardens, and disturbed soil, often in troops or lines. Distinguished from Coprinellus, Coprinopsis, and Parasola by their robust stature, shaggy cap scales, and non‑micaceous surface.