Molecular phylogeny of skipper butterflies (Lepidoptera: Hesperiidae) from the western ghats, India

Abstract

Butterflies and moths together comprise the second-most diverse order of insects on earth. Skipper butterflies (family Hesperiidae) form a natural biological link between butterflies and moths; they make up one of the largest families of butterflies, and are prominently represented in India’s Western Ghats biodiversity hotspot. However, their phylogenetic relationships with other Oriental Hesperiidae are poorly known, which prevents us from developing a biogeographic understanding of diversification of butterflies in the Western Ghats. Here we propose higher (genus-level) phylogenetic relationships of many Western Ghats butterflies of family Hesperiidae based on molecular sequence data from two genes: the mitochondrial cytochrome oxidase I (COI) and nuclear elongation factor-1α (EF-1α). Phylogenetic analyses with the Maximum Likelihood, Maximum Parsimony and Neighbor-Joining methods resulted in similar relationships at subfamily and genus levels. Monophyly of family Hesperiidae was strongly supported and relationship among the traditionally recognized subfamilies was as follows: (Coeliadinae + (Pyrginae + Hesperiinae)). Coeliadinae was found monophyletic and similarly, Hesperiinae was also found forming monophyletic group. Pyrginae was found to be paraphyletic with several clades. We resolved phylogenetic positions of many genera of the diverse tribe Baorini (Hesperiinae), which has many Western Ghats endemics. This work aims to build towards a fuller taxonomic and phylogenetic framework that will contribute to understanding when and how the Western Ghats butterfly fauna formed and diversified. It will also help identify taxonomically unique species and contribute to their conservation.