Tolypocladium reniformisporum sp. nov. and Tolypocladium cylindrosporum (Ophiocordycipitaceae, Hypocreales) co-occurring on Ophiocordyceps sinensis

Two Tolypocladium species, Tolypocladium reniformisporum sp. nov., and T. cylindrosporum , were isolated from the sclerotium of a naturally occurring Ophiocordyceps sinensis specimen in the Baima Snow Mountains of Deqin County, Yunnan Province in southwestern China. They were described and illustrated by morphological characters and growth-temperature relationships. Phylogenetic analyses based on a 5-gene (SSU, LSU , TEF, RPB1 , and RPB2 ) dataset and sequences of the internal transcribed spacer regions (ITS) showed that T. reniformisporum was phylogenetically closely related to T. cylindrosporum and other similar species. Tolypocladium reniformisporum was morphologically distinguishable from other Tolypocladium species because of its slow-growing colonies, short phialides, and smaller reniform conidia. Growth tests showed that the isolated T. reniformisporum and T. cylindrosporum strains were psychrotrophic, with optimal growth temperatures of 18–22 ℃, and minimum growth temperatures below 5 ℃.