Aphyllophoricolous Species of Hypomyces with KOH-Negative Perithecia

The aphyllophoricolous species of Hypomyces that have pallid, KOH-negative perithecia and Cladobotryum anamorphs form the biggest subset within the genus. Twelve holomorphic members and one asexual member of this group that occur in temperate regions of the northern hemisphere are discussed. Several new European collections are reported for H. albidus, H. orthosporus, H. polyporinus and H. semitranslucens. Hypomyces pseudopolyporinus, H. sympodiophorus and H. viridigriseus are presented from Europe for the first time. Two new species, H. corticiicola and H. rostratus, are described from Europe. Cladobotryum stereicola, for which no teleomorph is known, is not the anamorph of H. sympodiophorus, as has been reported. The new combination Cladobotryum uniseptatum is proposed for the anamorph of H. sympodiophorus. A previously unknown Cladobotryum anamorph is found associated with the teleomorph of H. tegillum in herbarium material from Central and South America. Hypomyces sibirinae, previously known only from its type location in Indonesia, is reported from North America. The role of anamorphic vs. teleomorphic characters and the use of ascospore measurements in delimitation of species and identification of specimens is discussed in the group of KOH-aphyllophoricolous Hypomyces.