Mitochondrial DNA Variation Within and Between Two Species of Neotropical Anopheline Mosquitoes (Diptera: Culicidae)

: We analyzed variation in mitochondrial DNA (mtDNA) of two neotropical mosquitoes, Anopheles rangeli (n = 181) and A. trinkae (n = 45), with very different distribution patterns in Latin America, to assess species boundaries for these putative sister taxa and to examine population genetic structure. Phylogenetic analyses revealed (1) support for the monophyletic origin of each species; (2) diagnostic restriction site differences between the species; (3) geographic partitioning of haplotypes by country in A. rangeli from Bolivia, Ecuador, and Venezuela compared with considerable overlap in haplotypes of A. trinkae from Bolivia and Ecuador; and (4) similar levels of mean haplotype and nucleotide diversity in both species, but lower levels of mean nucleotide divergence in A. trinkae compared with A. rangeli. We hypothesize that higher maternal gene flow and lower divergence in A. trinkae are most likely due either to a distinctive matrilineal history or to a smaller effective population size, which may have been influenced by a smaller, essentially linear geographic range along the eastern flank of the Andes. In the cladistic analysis of A. rangell, the Bolivian haplotypes appear to be more derived than those from Ecuador or Venezuela, yet there is no evidence to support the hypothesis of a recent range expansion from Ecuador into Bolivia.