The Species of Exidiopsis (Tremellaceae) of the U.S.S.R.

Abstract

SUMMARYThe species of Exidiopsis known to the authors from the U.S.S.R. are noted. Those species not previously studied in detail are described and illustrated. The genus Exidiopsis is emended to exclude the type and closely related species of Eichleriella. Exidiopsis candida, previously known only from tropical and subtropical regions, is shown to occur on Sakhalin Island. Exidiopsis effusa, on angiosperm wood, is reported from eastern Siberia and European U.S.S.R. Exidiopsis grisea, on gymnosperm wood, was identified from several sites in the Transcaucasia. A previously undescribed species, E. gypsea, is shown to occur in the Crimean Peninsula, Transcausasia, and Estonian S.S.R. Exidiopsis calcea is reported from throughout the U.S.S.R. and apparently occurs on both angiosperm and gymnosperm wood. It is the most frequently collected and widely distributed species of Exidiopsis in the U.S.S.R. Additional collections of E. griseobrunnea are noted from Siberia, and a new subspecies, E. griseobrunnea subsp. macrogyna, is described. Both subspecies of E. griseobrunnea are apparently only able to utilize species of Duschekia as a substrate. Additional collections of E. laccata and E. pallida, which have been previously reported from the U.S.S.R. were not noted.