Notes on SIMOCYBE in the Pacific Northwest
Prepared for the Pacific Northwest Key Council
By Ian Gibson, South Vancouver Island Mycological Society
Copyright ã 2019 Pacific Northwest Key Council
SIMOCYBE P. Karst.
Features include 1) small, mycenoid or collybioid or pleurotoid fruitbodies that are thin-fleshy to membranous, usually colored brown or with an olive tone, 2) a cap that is hemispheric to conic-campanulate, expanding, the surface more or less hygrophanous, 3) gills that are adnexed to almost free, to adnate or sinuate, 4) a rather thin stem, with conspicuous or inconspicuous basal mycelium, 5) a short-lived veil that is not prominent and not ring-like, practically absent in most species, 6) habitat on wood, sawdust, leaves and other plant debris, 7) a spore deposit that is ochraceous to somewhat olivaceous or brownish, 8) spores that are elliptic, oval, subfusoid, oboval to somewhat wedge-shaped, rarely over 9 um long, smooth, with a moderately thick wall that is distinctly to indistinctly double (episporium and endosporium), usually without, rarely with, a very small pore, 9) basidia 4-spored but sometimes 2-spored, 10) cheilocystidia present, usually making the edge of the gills heteromorphic, 11) pleurocystidia absent, 12) cap cuticle a trichoderm or a trichodermal palisade, with dermatocystidia, and 13) clamp connections generally present.
Simocybe is a mostly subtropical or tropical genus growing on wood, especially hardwood debris. A number of species undoubtedly occur in the Pacific Northwest but are sparsely documented. At the University of Washington there are collections from Washington labeled as Simocybe sumptuosa, S. centunculus, and S. serrulata, as well as other undifferentiated Simocybe collections. The University of British Columbia has collections from British Columbia labeled S. sumptuosa, S. centunculus, and S. rubi, (most by O. Ceska).
The following three descriptions are derived from Moser(1). Simocybe rubi has a 0.5-1.5cm cap colored clay-brown, clay-grey, grey-olive, that is granular-floury when young but becomes bald, gills more or less the same color as the cap, stem 0.05-0.4cm, excentric [off-center], whitish then brown, growth on dead hardwood branches, and spores 8-10 x 5.5-7 microns, pallid-brown, broadly elliptic, with a weak germ pore. Simocybe sumptuosa has a 1-4cm bald cap, when moist hardly sulcate, olive, olive-honey, when old also date brown, stem 1-4cm x 0.15-0.6cm, usually central, growth on hardwood tree stumps, spores 7-10(11) x 4-5.5 microns. Simocybe centunculus has a 1-2.5cm bald cap that is olive brown, convex then flat, gill edges yellowish-floccose or whitish-floccose, stem 1.5-3cm x 0.2-0.3cm, pruinose, usually central, growth on hardwood tree stumps and twigs, and spores 6-7.5 x 4-5 microns.
2. Singer, Rolf. 1986. The Agaricales in Modern Taxonomy 4th Edition. Koeltz Scientific Books, Koenigstein, Germany. 981 pp.