Systematic relationships among pocket gopher chewing lice (Phthiraptera: Trichodectidae) inferred from electrophoretic data.

Multilocus starch-gel electrophoresis was used to obtain electrophoretic data for maximum parsimony, phenetic, and component analysis of systematic relationships among 14 species of pocket gopher chewing lice and two outgroup species. Pocket gopher lice studied included taxa representing seven of the 25 species complexes in Geomydoecus, and two of the four species complexes of Thomomydoecus. In pairwise comparisons, 12 of the 14 pocket gopher lice were characterized by two or more fixed genetic differences, and each nominal species possessed at least one fixed difference. These electrophoretic results are consistent with previous morphological analysis of species-level taxonomy. A maximum-parsimony analysis of the electrophoretic data yielded 80 trees, each with a length of 78 steps and a consistency index of 0.83. The strict consensus tree and the UPGMA phenogram of genetic distances indicate that five species of lice from Central American pocket gophers (Orthogeomys) form a clade distinct from lice hosted by North American pocket gophers (Geomys, Thomomys, and Cratogeomys). Other louse clades receiving reasonable support in bootstrap parsimony analysis include: (Thomomydoecus wardi, Th. minor); (Geomydoecus scleritus, G. mobilensis); (G. panamensis, G. setzeri); and (G. cherriei, G. costaricensis). The systematic results of this electrophoretic study are generally consistent with the boundaries of louse species complexes described previously.