Verh. zool.-bot. Ges. Wein. 16: 45. 1866.
Common Name: none
Synonym: Pleurotus petaloides
Cap 3-6 cm broad, up to 8 cm long, fan-shaped to petaloid, margin incurved, undulate, splitting in dry weather; surface smooth, dry, dark-brown, fading to dull tan in age; flesh thin, pliant, with a gelatinous layer.
Gills decurrent to near the stipe base, crowded, white to greyish, narrow, edges finely pubescent.
Stipe eccentric, 1.5-5 cm long, 2-3 cm thick, tapering to the base; surface pallid to dull tan, densely pubescent, thickened white mycelium (rhizomorphs at the base); veil absent.
Spores 7-8.5 x 4.5-5 µm, elliptical, smooth, nonamyloid; spore print white.
Solitary, scattered to clustered in lignicolous-rich soils or wood chips; fruiting from late summer in watered areas to mid-winter.
Edible, but of little culinary value.
This oyster mushroom look-alike was once placed in Pleurotus, but was moved into its own genus because the cap was shown to have a distinctive gelatinous layer and the gills, large, thick-walled cheilocystidia. The latter character, which gives the gill edges a pubescent aspect, plus the tendency to grow on wood chips as opposed to logs, helps to distinguish it from Pleurotus ostreatus and its close relatives. Tapinella panuoides, another Pleurotus look-alike, is also occasionally found in wood chips. It, however, has a yellowish-brown cap and gills, the latter which are easily separated from the cap, and yellowish to pale-buff spores.
Desjardin, D.E., Wood, M.G. & Stevens, F.A. (2015). California Mushrooms: The Comprehensive Identification Guide. Timber Press: Portland, OR. 560 p.
Smith, A.H. (1949). Mushrooms in their Natural Habitats. Sawyer's Inc: Portland, OR. 626 p.
Thorn, R.G. & Barron, G.L. (1986). Nematoctonus and the tribe Resupinateae in Ontario, Canada. Mycotaxon 25(2): 321-452