Molecular Systematics of Members of the Notropis dorsalis Species Group (Actinopterygii: Cyprinidae)

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))).

Fig. 1.

Strict consensus of two equally parsimonious trees produced by the primary unweighted analysis of the data (1735 steps, CI = 0.367, RI = 0.648). Numbers above internodes refer to the number of unambiguous changes on that node and (in parentheses) Bremer support indices. Numbers below internodes refer to bootstrap values (10,000 replicates). Nodes with bootstrap values < 50% were not labeled

Fig. 2.

Single most-parsimonious resolution produced by weighting transversions 3 times transitions in the primary analysis. Numbers above internodes refer to the number of unambiguous changes on that node and (in parentheses) Bremer support indices. Numbers below internodes refer to bootstrap values (10,000 replicates). Nodes with bootstrap values < 50% were not labeled

Fig. 3.

Strict consensus of two equally parsimonious resolutions produced by the secondary unweighted analysis of the data (1113 steps, CI = 0.482, RI = 0.828). Numbers above internodes refer to the number of unambiguous changes on that node and (in parentheses) Bremer support indices. Numbers below internodes refer to bootstrap values (10,000 replicates). Nodes with bootstrap values < 50% were not labeled

Fig. 4.

Single most-parsimonious resolution produced by weighting transversions 3 times transitions in the secondary analysis. Numbers above internodes refer to the number of unambiguous changes on that node and (in parentheses) Bremer support indices. Numbers below internodes refer to bootstrap values (10,000 replicates). Nodes with bootstrap values < 50% were not labeled

Accepted: 02 Mar 2001