Coprinellus

Coprinellus is a genus of fungi in the family Psathyrellaceae, comprising a diverse group of small, saprotrophic mushrooms commonly found in decaying wood, leaf litter, and other organic-rich environments. The genus was established to distinguish certain deliquescent species previously classified under Coprinus, characterized by their cap morphology and spore features.

Members of Coprinellus are typically diminutive, with cap diameters ranging from a few millimeters to several centimeters. The caps are often conical or bell-shaped in youth, becoming more flattened or viscid with age, and may display various colors including tan, brown, or gray. A distinctive feature of many species is their gills, which often deliquesce or dissolve into an inky black liquid as they mature.

The spores of Coprinellus are usually dark-colored, smooth, and ellipsoid or almond-shaped, which aids in species identification. Microscopic features, such as the presence of specific cystidia and the structure of the hyphal system, are also important for taxonomy.

Coprinellus species are generally not considered edible due to their small size, potential toxicity, or unpalatability, and some species resemble toxic inky caps. They are of interest primarily to mycologists studying fungal diversity and taxonomy, as well as ecological researchers investigating decomposition processes.

The genus is distributed worldwide, with a higher diversity found in temperate regions. Ongoing molecular studies continue to refine the classification within Psathyrellaceae, leading to the redefinition and discovery of new species, including those within Coprinellus.