Tenuimyces S.L. Liu & L.W. Zhou, gen. nov.
Index Fungorum number: IF 901051; Mycobank number: MB 901051; Facesoffungi number: FoF 14801.
Etymology – Tenuimyces (Lat.) referring to thin basidiomes.
Diagnosis – Distinguished from other genera in Cystostereaceae by extremely thin basidiomes, a monomitic hyphal system, the presence of cystidioles and hyphidia, and aculeate, slightly thick-walled basidiospores.
Basidiomes annual, resupinate, effused, thin, up to 50 μm thick in section. Hymenophore smooth, white to cream. Margin thinning or indeterminate, concolorous or paler. Hyphal system monomitic; generative hyphae with clamp connections, hyaline, thin-walled. Cystidioles and hyphidia present. Basidia subclavate, 4-sterigmate. Basidiospores broadly ellipsoid, hyaline, aculeate, slightly thick-walled, IKI–, CB–.
Type species – Tenuimyces bambusicola S.L. Liu & L.W. Zhou.
Notes – Three corticioid specimens from Southwest China form a distinct lineage with strong support within Cystostereaceae in phylogenetic analysis (Fig. 1). Morphologically, these three specimens have smooth hymenophore, a monomitic hyphal system, aculeate, slightly thick-walled basidiospores that are distinguished from known genera in Cystostereaceae (Song et al. 2018c). Therefore, a new genus Tenuimyces is described on the basis of these three specimens.
Species