Department of Plant Pathology, 1453 Fifl eld Hall, University of Florida Gainesville, Florida 32611-0680 U.S.A.

E-mail: [email protected] .edu

Recent molecular studies have resulted in the publication of a phylogenetically based classi cation of the fungi. e organisms formerly included in the Trichomycetes and Zygomycetes are dispersed into four subphyla containing one to four orders: 1) Entomophthoromycotina (Entomophthorales), 2) Kickxellomycotina (Asellariales, Dimargaritales, Harpellales, Kickxellales), 3) Mucoromycotina (Endogonales, Mortierellales, Mucorales) and 4) Zoopagomycotina (Zoopagales). Two families are included in Harpellales (Harpellaceae, Legeriomycetaceae) and Mucorales (Mucoraceae, Umbelopsidaceae), five in the Zoopagales (Cochlonemataceae, Helicocephalidaceae, Piptocephalidaceae, Sigmodeomycetaceae, Zoopagaceae) and six in the Entomophthorales (Ancylistaceae, Basidiobolaceae, Completoriaceae, Entomophthoraceae, Meristracraceae, Neozygitaceae). Each genus is listed under its respective family. Each taxon includes a citation and one or more critical references. Information is given on the ecology, classi cation and phylogeny of zygomycetous fungi. e Zygomycota are not included in a phylum because too little is known about their phylogeny to make this determination.