Marasmius curreyi

Pileus
Cap 4.0-8.0 mm broad, convex, becoming plano-convex to plane in age, sulcate-striate, the disc depressed to umbilicate; margin at first incurved, then decurved, eventually level to raised, occasionally wavy; surface finely tomentose with a hand-lens, rust-brown, fading to orange, pinkish-tan or pale-tan, darkest at the disc and ribs; context membranous, cream-colored; odor and taste mild; fruiting body reviving after drying.

Lamellae
Gills distant, attached to a collarium, not directly to the stipe, cream-colored, relatively broad, up to 2 mm in width, sometimes intervenose, the edges occasionally marginate towards the cap margin, if so, then colored like the cap; lamellulae typically absent.

Stipe
Stipe 1.5-3.0 cm long, less than 1 mm thick, filiform, hollow, more or less equal, frequently bent to undulate; surface glabrous, pallid at the apex, elsewhere blackish-brown, the base slightly swollen and subtend by short dark fibrils, instititious; partial veil absent.

Spores
Spores 9.0-12.0 x 4.0-5.0 µm, elliptical to elliptical-oblong in face-view, inequilateral in profile with a flat and curved side; spores thin-walled, hyaline, with vacular inclusions, hilar appendage inconspicuous, inamyloid; spore print not seen.

Habitat
Gregarious, in lawns, fruiting from dead grass stems (culms); appearing during the summer months; widely distributed; rare.

Edibility
Unknown; too small to have culinary value.

Comments
Hidden among blades of grass and below the level of mower blades, fruits a tiny and seldom collected Marasmius, M. curreyi. This liliputian species is recognized by a orange-brown, pinkish-brown to buff, sulcate-striate, often umbilicate cap, and bristle-like stipe. Records would suggest that it is among the rarest of California fungi but considering its ubiquitous substrate, it's more likely that it's simply overlooked. It often fruits simultaneously with several other lawn fungi including Panaeolus foenisecii, Conocybe lactea, Agrocybe pediades, and Coprinopsis friesii. Marasmius curreyi is most likely to be confused with another rare Marasmius, M. armeniacus. It also occurs on grass culms and has similar cap colors, but the latter lacks the depressed to umbilicate cap disc of M. curreyi, the gills attach directly to the stipe not via a collarium, and has a paler, non-institious stipe.