Mycologia 97(3): 677. 2005.
Common Name: garlic mushroom
Synonym: Marasmius copelandii Peck
Misapplied name: Marasmius scorodonius
Cap 0.5-2.0 cm broad, convex, expanding to nearly plane at maturity, sometimes slightly umbonate; margin decurved, striate-wrinkled up to two-thirds the distance to the disc; surface more or less glabrous, brown, shading to pale-tan at the margin, in age more uniformly brown, occasionally fading to nearly white; context less than 1 mm thick, colored like the cap; odor of garlic, taste: pungent.
Gill adnate, adnexed, sometimes seceding, thin, close, lamellulae 1-2 seried, cream-buff, darkening to tan-buff.
Stipe 3-8 cm long, 1-3 mm thick, slender, straight, more or less equal, hollow at maturity; surface tomentose, mahogany-brown at the base, tan-buff at the apex; stipe base not instititious; veil absent.
Spores 13-18 x 2.5-3.5 µm, narrowly tear-shaped, smooth, nonamyloid; spore print whitish.
Scattered to gregarious in mixed hardwood-conifer woods; common on leaf duff of oaks (Quercus spp.) and tanbark oak (Lithocarpus densiflora); fruiting from early to mid-winter.
Edible; used as a seasoning according to Arora.
Mycetinis copelandii, though small and drab, is not just another little brown mushroom. It's hallmark is a garlic odor so strong that it is frequently found by smell rather than sight. A striate-wrinkled cap, pubescent, two-toned stipe, and preference for oak/tanbark oak leaves, help to distinguish it from other garlic-odored species. Marasmius scorodonius is similar but has a glabrous stipe and fruits on different substrates. According to Desjardin, it is rare in California.
Desjardin, Dennis E. (1987). The Agaricales (Gilled Fungi) of California. 7. Tricholomataceae I. Marasmioid Fungi. Mad River Press: Eureka, CA. 100 p.
Desjardin, Dennis E. (1987). New and Noteworthy Marasmioid Fungi from California. Mycologia 79: 123-134.
Desjardin, D.E., Wood, M.G. & Stevens, F.A. (2015). California Mushrooms: The Comprehensive Identification Guide. Timber Press: Portland, OR. 560 p.
Peck, C.H. (1904). New species of fungi. Bull. Torrey bot. Club 31(4): 177-182. (Protologue)
Wilson, A.W. & Desjardin, D.E. (2005). Phylogenetic relationships in the gymnopoid and marasmioid fungi (Basidiomycetes, euagarics clade). Mycologia 97(3): 667-679.