Phylogenetic systematics of the major lineages of pannote mayflies (Ephemeroptera : Pannota)

The phylogeny of 14 monophyletic groupings of known pannote mayfly genera a re presented based on a cladistic analysis. From this, a strictly phylogene tic hierarchical classification of supergeneric taxa is presented, and prev ious paraphyletic and polyphyletic concepts in the Pannota are corrected. R evised superfamilies, families, and subfamilies are described, illustrated, and discussed in terms of makeup, distribution, and diagnosis. Superfamili es represent the two major cosmopolitan clades: Caenoidea (divided into sis ter clades recognized as the Caenidae and Neoephemeridae) and Ephemerelloid ea (further divided into a sequential series of clades recognized at the fa mily rank and including Ephemerellidae, Austremerellidae, n. stat., Telogan odidae (restricted), Teloganellidae, n. fam., Ephemerythidae, n. stat., Mac hadorythidae, n. stat., Tricorythidae (restricted), and the measurably most apotypic pannote family Leptohyphidae. The first major branching within th e Ephemerelloidea results in a Laurasian clade (Ephemerellidae sensu strict o) and all other lineages, which constitute a Gondwanan clade. Such vicaria nce suggests a Pangaean origin about 200 million years old for the Ephemere lloidea, and probably an even older origin for Pannota. A sequence of linea ges in Caenidae are recognized as the Caeninae, Madecocercinae, n. subfam., and Brachycercinae (restricted); sister lineages in the Ephemerellidae are recognized as the Ephemerellinae (restricted) and Timpanoginae, n. stat.; and sister lineages in Tricorythidae are recognized as Tricorythinae and Di cercomyzinae. Ranorythinae and Madecassorythinae are provisionally placed a s synonyms of Tricorythinae and Dicercomyzinae, respectively, because of la ck of larval data associated with them. The unrelated families Prosopistoma tidae and Baetiscidae must be excluded from the Pannota. Taxonomic keys are constructed to superfamilies, families, and subfamilies of Pannota for bot h known larvae and adults.