Phylogenetic position of Drosophila bocainensis (Diptera, Drosophilidae) in the willistoni group and the paraphyletic status of the bocainensis subgroup

Abstract

The willistoni group of Drosophila is subdivided into the alagitans, bocainensis and willistoni subgroups, and has been an important model for studying evolutionary processes in the Neotropics for decades. Phylogenetic studies place the bocainensis subgroup as a grade in relation to the monophyletic willistoni subgroup, although these included molecular or morphological data for up to four species of the 12 species included in the first subgroup. Here, we characterized the first nucleotide sequences for three mitochondrial and five nuclear genes of Drosophila bocainensis Pavan & da Cunha, 1947, and employed these for addressing the paraphyly of this subgroup under a coalescent approach. Our results still recovered this paraphyletic relationship, placing D. bocainensis, D. capricorni Dobzhansky & Pavan, 1943 and D. sucinea Patterson & Mainland, 1944 in a basal clade, which diverged around 6.81 million years ago. The relationship of D. nebulosa Sturtevant, 1916 and D. fumipennis Duda, 1925 as a sister clade to the willistoni subgroup was recovered. The possible causes of such paraphyly are discussed.