Group of Fungi: Agarics

Family: Marasmiaceae

Latin Name: Marasmius rotula (Scop.) Fr.

Common Name: Pinwheel Marasmius

Description: Total height 1 1/4–2 3/4 in (3–7 cm); cap 1/4–5/8 in (0.5–1.5 cm) wide, radially striate, the striations sunken and giving the cap the appearance of being pleated, cap with a shallow, navel-like depression at the center, surface smooth, light yellowish-brown to yellow-white or white, margin wavy; gills widely separated, white; stalk 1–2 1/2 in (2.5–6.5 cm) long, 1/64–1/32 in (0.05–0.1 cm) in diameter, tough, white above and dark blackish-brown below; spores white in mass.

Biological Role: Decomposer of twigs and other woody debris from broadlead trees.

Habitat: On the ground in broadleaf forests; usually occurring in small groups.

Geographical Distribution: Found throughout eastern North America.

Comments: This small fungus has the unusual feature, shared with other species in the same genus, of being able to shrivel up during periods of dry weather and then revive in response to the return of moist conditions. Marasmius capillaris is very similar to Marasmius rotula but occurs on decaying oak leaves.