Marasmius sullivantii

[ Basidiomycetes > Agaricales > Marasmiaceae > Marasmius . . . ]

by Michael Kuo

This attractive little Marasmius is quite common in my area (central Illinois), where oak-hickory woods predominate, in early summer. I often find it growing gregariously under White Oak. Its stem is fairly smooth, though it may have a faint bloom at first, or maintain a copious pad of whitish basal mycelium where it attaches to leaves, sticks, and other woody debris. The cap is reddish orange, and only faintly lined at the margin.

Microscopic features that help to define Marasmius sullivantii (they should probably be checked before betting the house on your identification) include the spore size (7-9 x 3-3.5 µ) and the presence of variously shaped cystidia (special sterile cells) on the gills, measuring about 16-38 µ in length--barely longer than the basidia.

I have no information on the edibility of Marasmius sullivantii, but it is too small to consider for the table, anyway.

Description:

Ecology: Saprobic on leaf litter and woody debris in hardwood forests; growing alone or gregariously; summer and fall; east of the Mississippi River.

Cap: To 2.5 cm across; convex, becoming flat; not pleated; typically smooth overall and faintly lined at the margin; dry; reddish orange or rust-colored.

Gills: Attached to the stem or free from it; close; white or with the edges faintly pinkish at first.

Stem: 5-2.5 cm long; 1-1.5 mm thick; equal; dry; wiry; sometimes with a faint bloom or dusting at first, but soon smooth; often with copious white basal mycelium; white or nearly clear at the apex, reddish to orangish in the midsection, reddish brown to black below.

Flesh: Thin; insubstantial.

Odor and Taste: Taste mild or slightly bitter; odor not distinctive.

Spore Print: White.

Microscopic Features: Spores 7-9 x 3-3.5 µ; smooth; elliptical. Cystidia versiform; 16-38 x 3-7 µ. Broom cells present in pileipellis.

REFERENCES: Montagne, 1856. (Saccardo, 1887; Gilliam, 1976; Smith, Smith & Weber, 1979; Phillips, 1991/2005; Horn, Kay & Abel, 1993.) Herb. Kuo 04309501, 06100301, 07220308, 05290404, 06280701.

Compare with Marasmius pyrrhocephalus, which has a densely hairy, tough, darker stem; it lacks broom cells in the cap cuticle.

Further Online Information:

Marasmius sullivanti [sic] at Roger's Mushrooms

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Cite this page as:

Kuo, M. (2004, November). Marasmius sullivantii. Retrieved from the MushroomExpert.Com Web site: http://www.mushroomexpert.com/marasmius_sullivantii.html