Coprinus

Coprinus is a genus of fungi in the family Psathyrellaceae. Historically, Coprinus comprised a large and heterogeneous group of gilled mushrooms known as ink caps, many of which display deliquescence—the cap and gills dissolve into a black, inky liquid as they mature. The most familiar member is Coprinus comatus, the shaggy mane, a tall, white mushroom with a shaggy cap. Other well-known ink caps have been described under Coprinus but have since been moved to Coprinellus, Coprinopsis, or Parasola following molecular studies. The type species is Coprinus comatus.

These fungi are saprotrophic, growing on rich soils, leaf litter, manure, wood chips, and other decomposing plant material. They are found worldwide, especially in temperate regions, often appearing after rain in grassy areas or gardens. They produce a black spore print.

In terms of chemistry and toxicity, several ink caps produce coprine, a compound that can cause adverse reactions when consumed with alcohol. The best-known example is Coprinus atramentarius (often placed in Coprinopsis atramentaria), widely called the common ink cap or tippler's fungus. Because of this, alcohol should be avoided for a period after eating certain ink caps. Not all Coprinus species share this trait, and edibility varies; some young specimens are eaten in parts of their range, notably Coprinus comatus, which is often regarded as edible when young and properly prepared.

Taxonomic revision: due to DNA evidence, many species formerly placed in Coprinus have been reassigned to other genera. The name Coprinus today refers mainly to a small core group, with the remaining ink caps distributed among Coprinellus, Coprinopsis, and Parasola. The genus Coprinus thus serves as a historical umbrella for a diverse set of inky caps rather than a single cohesive lineage.