Hydrophana V. Malysheva & Spirin

Hydrophana V. Malysheva & Spirin View in CoL View at ENA , Nordic Journal of Botany 37 (e 02394): 8, 2019, emend.

Description.

Basidiocarps effused, continuous, smooth or tuberculate, gelatinous, thin. Hyphal structure monomitic; hyphae clamped. Cystidia absent; hyphidia present, richly branched, 0.5–1.5 μm in diam. Basidia four-celled, longitudinally septate, broadly ellipsoid to globose, pedunculate (stalk occasionally reduced). Basidiospores hyaline, thin-walled, broadly cylindrical or broadly ellipsoid to globose. On rotten wood.

Type species.

Sebacina sphaerospora Bourdot & Galzin.

Originally, Hydrophana was introduced to encompass one species, H. sphaerospora (Bourdot & Galzin) Malysheva & Spirin (formerly Myxarium sphaerosporum (Bourdot & Galzin) D. A. Reid ), which turned out to be not closely related to the rest of the Myxarium - like taxa. Morphologically, Hydrophana was distinguished from Myxarium s. lato mainly due to broadly ellipsoid or subglobose basidiospores in the type species ( Spirin et al. 2019 b). However, adding two new Hydrophana species with broadly cylindrical or ellipsoid basidiospores necessitates a redefinition of the genus. In its current scope, Hydrophana can be separated from the ellipsoid-spored Myxarium spp. due to continuous (not reticulate or pustulate-coalescing) basidiocarps, smooth (or nearly so) hymenophore, narrower hyphidia, and slenderer sterigmata. The two latter features can be used for distinguishing Hydrophana spp. from Ofella glaira (Lloyd) Spirin & Malysheva. In turn, Myxariellum spp. have well-differentiated tapering cystidia, and their basidia possess a thicker stalk and wider sterigmata than do Hydrophana .