Community find

Mica Cap

Coprinellus micaceus

Group

gilled mushroom

Spore print

Black or very dark brown.

Size

Cap diameter 2-5cm; Stipe 4-10cm height x 0.2-0.5cm width.

Season

Spring through autumn, often appearing shortly after rain showers.

Habitat

Grows in dense clusters on or near decaying wood, often at the base of broadleaf trees, stumps, or from buried roots in lawns and gardens.

Distribution

Cosmopolitan; widely distributed throughout North America, Europe, and parts of Asia and South America.

Key characteristics

Bell-shaped cap that is tawny-brown, often covered in tiny glistening salt-like granules (mica) when young. The cap has distinctive radial grooves or striations extending from the margin toward the center.

Fruiting body

Cap is 2-5cm wide, initially oval then bell-shaped, honey-brown to ochraceous. Gills are free or narrowly attached, crowded, white then turning brown and finally black as they deliquesce (autodigest). Stipe is 4-10cm long, 2-5mm thick, white, hollow, and fragile.

How to recognise it

Look for the dense clustering habit, the fine glistening particles on the cap of young specimens, and the deeply striate (grooved) cap margins.

Look-alikes

Coprinellus truncorum (nearly identical without microscopy), Coprinellus radiates, and Coprinopsis atramentaria (which is larger and lacks the glistening granules).

Ecological role

Saprophytic, acting as a primary decomposer of hardwood organic matter.

Notes

This species is part of the 'inky cap' group, named for their unique process of deliquescence where the gills digest themselves into a black liquid to help disperse spores in humid conditions.