Panaeolus foenisecii
Panaeolus foenisecii, commonly called the haymaker's panaeolus, lawnmower's mushroom, mower's mushroom, haymaker, or brown hay mushroom, is a very common and widely distributed little brown mushroom often found on lawns. It is not edible.
Description
The cap is 1 to 4 cm across, conic to convex, hygrophanous with a brownish colour when moist and tannish when dry, often with a dark band around the margin which fades as the mushroom dries.The gills are broad, adnate, brown with lighter edges, becoming mottled as the spores mature. The spore print is deep brown, sometimes purplish.
The stipe is 3 to 8 cm by 1 to 3 mm, fragile, hollow, beige to light brown, fibrous, pruinose, and slightly striate.
It has a slightly unpleasant nutty fungal taste. The odor is nutty and slightly unpleasant.
Microscopic features
Spores measure 12–17 x 7–11 μm, subfusoid to lemon shaped, rough, dextrinoid, with an apical germ pore. Cheilocystidia subfusoid to cylindric or subcapitate, often wavy, up to 50 μm long. Pleurocystidia absent, but some authors report inconspicuous "pseudocystidia". The pileipellis a cellular cuticle with subglobose elements and has pileocystidia.Similar species
Similar species include Agaricus campestris, Conocybe apala, Marasmius oreades, Psathyrella candolleana, and Psathyrella gracilis.It is sometimes mistaken for the psychedelic Panaeolus cinctulus or P. olivaceus, both of which share the same habitat and can be differentiated by their jet black spores. This is probably why P. foenisecii is occasionally listed as a psychoactive species in older literature.