<i>Zygopolaris</i> , A New Genus of Trichomycetes Producing Zygospores with Polar Attachment

SUMMARYA new monotypic genus of the fungal order Harpellales (Genistella- ceae) has been found in three localities in the United States inhabitating the guts of mayfly nymphs, Ephemerella and Baetis. Mature sporulating thalli of Zygopolaris ephemeridarum may be found protruding from the the anus of the host into the aquatic environment. Released trichospores do not appear to have basal appendages, as do most other Harpellales, but evidence of rudimentary appendage formation has been found in the generative cells. Zygospores are attached at one pole, and resemble those of Carouxella (Harpellaceae). The similarities of the two genera and two families are discussed, as well as the four types of zygospores recognized in the Harpellales.