Wild species

Ovoid

Psilocybe ovoideocystidiata

aka River teacher · Psilocybe ovoideocystidiata

A springtime wood-lover first described in 2001, common along Midwestern and mid-Atlantic riverbanks and increasingly reported in urban mulch beds. Notable for fruiting months earlier than most temperate Psilocybe species.

Field marks

Convex to umbonate cap
Chestnut to cream colouring
Blue-green bruising
Variable partial veil
Rhomboid spores
Floodplain wood debris

Habitat

Woody debris and wood chips in floodplains, riverbanks, and overflow areas, plus suburban mulch beds, from Missouri and Georgia north to Michigan and east to Rhode Island, with a stronghold in the Ohio River valley. Fruits mid-April through late June — unusually early for the genus.

Relative potency

moderateRelative only — this guide gives no dosing guidance.

Lookalikes — read this twice

Psilocybe caeruleorhiza is a close relative lacking a persistent ring and fruiting in fall rather than spring. It is also confused with the smaller Psilocybe caerulipes, separable by this species' larger size, rhomboid spores, and earlier season. As with any wood-debris mushroom in riparian hardwood habitat, deadly Galerina marginata grows on the same logs and mulch and must be ruled out by spore print and bruising.

Deadly species grow in the same places as psilocybin ones and can resemble them closely. Never eat a wild mushroom identified from a website — including this one.