Phylogenetic analyses based on complete nucleotide sequences of the mitochondrial cytochrome b gene were performed to determine generic assignment and composition of the Notropis dorsalis species group (Hybopsis vs Notropis) and to determine relationships among the five species within this group. Phylogenetic relationships were reconstructed at two levels: (1) a primary analysis of 14 species of shiners to determine placement of the N. dorsalis species group with respect to other shiner species and to determine whether the closely related Notropis buccatus is a member of this group; and (2) a secondary analysis of 32 individuals from the N. dorsalis species group to determine relationships among component species. In the primary analysis, the N. dorsalis species group was placed within genus Notropis, and N. buccatus was resolved as a member of the N. dorsalis species group. The within-species group phylogeny produced by the secondary analysis suggested a sister relationship between N. dorsalis and N. buccatus. This clade was found to be sister to remaining members of the N. dorsalis species group: (Notropis sabinae (Notropis longirostris (Notropis ammophilus and Notropis rafinesquei))).