Leucopaxillus laterarius

[ Basidiomycetes > Agaricales > Tricholomataceae > Leucopaxillus . . . ]

by Michael Kuo

Leucopaxillus laterarius decomposes leaf litter in eastern North America's hardwood forests. Its physical features are virtually inseparable from those of the conifer-loving Leucopaxillus albissimus, though the latter species is usually a little stockier, has slightly less crowded gills, and usually features less pink in the cap color (when pigments are present; both species are frequently white). Spore size may be a more reliable separator (the spores of Leucopaxillus laterarius are almost always under 5.5 µ long), but confusing laterarius-or-albissimus specimens should be expected if you are unwilling to accept my hardwood-conifer species division.

Description:

Ecology: Saprobic, decomposing the litter of hardwoods in oak and beech forests; growing scattered or gregariously; widely distributed in eastern North America; frequently appearing in early summer, but also common in late summer and fall.

Cap: 4-20 cm; convex with an inrolled margin when young, becoming broadly convex or flat; dry; smooth or very finely velvety (like kid leather), sometimes becoming patchy (but not truly scaly) over the center with age; white, pinkish, buff, or pale tan; the margin often broadly lined.

Gills: Attached to the stem or running down it; crowded; separable from the cap as a layer; whitish to dirty yellowish when mature.

Stem: 4-11 cm long; up to 2 cm thick at the apex; when young often slightly swollen near the base but by maturity usually more or less equal; smooth or very finely hairy; whitish; with prominent and copious basal mycelium.

Flesh: White; thick; hard; not changing on exposure.

Odor and Taste: Odor mealy or foul (like coal tar or swamp gas); taste mild or bitter.

Spore Print: White.

Chemical Reactions: Cap surface pale olive with KOH.

Microscopic Features: Spores 3.5-5.5 x 3.5-5 µ (including ornamentation); short-elliptical or nearly round; spiny with amyloid warts. Cheilocystidia absent or scattered. Pleurocystidia absent.

REFERENCES: (Peck, 1873) Singer & Smith, 1943. (Kauffman, 1918 [as Tricholoma acerbum]; Singer & Smith, 1943; Smith, Smith & Weber, 1979; McKnight & McKnight, 1987; Miller & Miller, 2006.) Herb. Kuo 09230602.

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Cite this page as:

Kuo, M. (2007, February). Leucopaxillus laterarius. Retrieved from the MushroomExpert.Com Web site: http://www.mushroomexpert.com/leucopaxillus_laterarius.html