Molecular systematics of the North American chub genus Macrhybopsis (Teleostei: Cyprinidae).

The North American fish genus Macrhybopsis (Teleostei: Cyprinidae) as presently conceived comprises 12 species and occurs in much of interior eastern North America. Variation in the mitochondrial ND2 gene and the nuclear S7 intron 1 reveal conflicting gene-tree relationships for deeper nodes, which are assumed to represent past introgression and heterospecific mitochondrial fixation. The results support monophyly for the wide-ranging M.

Molecular systematics and historical biogeography of the Nocomis biguttatus species group (Teleostei: Cyprinidae): nuclear and mitochondrial introgression and a cryptic Ozark species.

The Nocomis biguttatus species group ranges widely across North America from the Red River in Oklahoma and Arkansas north to Minnesota and east-west from Wyoming to Ontario. The group includes three traditionally recognized allopatric species: the wide-ranging N. biguttatus and two geographically more restricted species, N.

Systematics of the subgenus Oligocephalus (Teleostei: Percidae: Etheostoma) with complete subgeneric sampling of the genus Etheostoma.

The genus Etheostoma is the most diverse clade of freshwater fishes in North America. While studies have been performed with complete sampling of a single subgenus, none have included representatives of all remaining subgenera. The subgenus Oligocephalus is the largest, consisting of 25-27 species in four species groups, and its monophyly has never been clearly demonstrated.