Systematics, cladistics and biogeography of the American genus Farrodes (Ephemeroptera : Leptophlebiidae : Atalophlebiinae)

Cladistic and biogeographic analyses of the genus Farrodes are presented. T wo species groups are delineated within Farrodes: F. caribbianus and F. bin aculatus. Three species formerly placed in other genera-Thraulus caribbianu s Traver, Thraulus roundsi Traver and Homothraulus maculatus (Needham & Mur phy)-are transferred to Farrodes. The species of the F. carribbanus species group are revised. Three new species are described: F. savagei from Venezu ela, F. maya and F. mexicanus from Mexico. Keys to separate the two species groups of Farrodes and the species of the F. carribbanus species group are provided. Successive cladistic analyses were carried out on both adult and nymphal characters using Hennig86 and CLADOS. The matrix was composed of a ll available data (nymphal characters were missing for some species), from nymphal and adult stages separately and on taxa represented by both adult a nd nymphal characters. Species of the genera Simothraulopsis and Homothraul us (components of the Farrodes lineage) were included in the analyses, and Ecuaphlebia was used as the outgroup. Results of the four analyses are comp atible. The historical biogeography of Farrodes, with a distribution from n orthern Argentina to southern Texas, is analysed using the program COMPONEN T. Areas of endemism are established, and some of their relationships compa red with those of other groups available in the literature. (C) 1999 The Li nnean Society of London.