Molecular phylogeny of melanopline grasshoppers (Orthoptera: Acrididae):: The genus Melanoplus

A molecular phylogenetic analysis of several species of Melanoplus was undertaken to clarify the taxonomic relationships among members of this very large North American grasshopper genus. The study tested the validity of several long-standing morphologically based "species-groups." To achieve these goals, portions of 3 mitochondrial genes (cytb, COII, and 16S ribosomal RNA) were sequenced and phylogenetically analyzed using (weighted and unweighted) parsimony and neighbor-joining methods. Agreement with many of the groupings suggested by the early orthopterists was mixed, as illustrated by the following assemblages, emerging with varying levels of bootstrap support: (1) ([([sanguinipes, femurrubrum], devastator), brumeri], dawsoni); (2) ([packardii, foedus], angustipennis); (3) (bivittatus, differentialis); (4) (infantilis, alpinus); (5) (kennicotti, bowditchi); and (6) (confusus, occidentalis). Some support for the claim that the group Marginatus constituted the most "primitive" species-group was provided by the basal position occupied by its nominate species. A suggestion by Vickery that diversity within Melanoplus is sufficiently large to warrant division is discussed.