Little nest polypore

Appearance

Ecology: Saprobic on the deadwood of hardwoods (primarily elms); annual; causing a white rot; growing in clusters on branches, logs and stumps; spring through fall; widely distributed from the Great Plains eastward.

Fruiting Body: At first cup-like; developing a cap as an extension of the cup.

Cups: Saucer- to cup-shaped; to about 15 mm wide; upper surface white to brown, usually with zones of color, smooth; undersurface white; with a tiny stem-like structure.

Cap: Up to 5 cm across and 3 cm deep; semicircular, irregularly bracket-shaped, or kidney-shaped; occasionally fusing laterally with other caps; bald; radially furrowed and wrinkled; whitish to pale brownish; with concentric zones of color.

Pore Surface: Whitish, becoming a little yellowish with age; with 2-4 circular to angular pores per mm; tubes to 2 mm deep.

Flesh: White; fairly tough.

Odor and Taste: Not distinctive.

Chemical Reactions: KOH on flesh negative to yellowish.

Spore Print: White.

Microscopic Features: Spores 5-7 x 1.5-2 µ; smooth; cylindric; inamyloid. Cystidia absent. Hyphal system trimitic. Asexual spores produced by cups rod-shaped; 3-8 x 3 µ.

Naming

Synonyms:
Boletus conchifer Schwein., 1822
Coriolus conchifer (Schwein.) G. Cunn., 1949
Microporus conchifer (Schwein.) Kuntze, 1898
Polyporus conchifer (Schwein.) Fr., 1828
Polystictus conchifer (Schwein.) Sacc., 1888
Trametes conchifer (Schwein.) Pilát, 1939