title: Phylogeny of Powellomycetaceae fam. nov. and description of Geranomyces variabilis gen. et comb. nov.
abstract: The genus Powellomyces was described to accommodate two monocentric chytrid species from soil that develop exogenously and possess zoosporic ultrastructure similar to other members of the order Spizellomycetales. Despite Powellomyces-like chytrids being commonly observed in gross culture, the genus contained only two species. To determine diversity in this group I amassed 49 isolates of Powellomyces-like chytrids, including the cultures upon which species types were based and new isolates from pollen-baited water cultures of soils, plant detritus and manure. I sequenced portions of nucSSU and nucLSU rDNA regions and the EF-1α-like gene from each isolate to produce a molecular phylogeny. This phylogeny supports monophyly of spizellomycetalean chytrids with exogenous development and suggests that multiple distinct lineages exist within this group. This phylogeny, along with a reevaluation of the ultra-structural features of the two described species, supports the recognition of a new family, Powellomycetaceae, and genus, Geranomyces, which contains 31 isolates of G. variabilis comb. nov.
authors.affiliation: School of Biology & Ecology, University of Maine, 5722 Deering Hall, Orono, Maine 04469, USA. david.r.simmons@umit.maine.edu
authors.forename: D Rabern
authors.initials: DR
authors.lastname: Simmons
mesh_terms: D005658:Fungi / Q000145:classification* / Q000648:ultrastructure; D010802:Phylogeny