Sequence evolution among divergent mitochondrial haplotypes within species of Junonia butterflies

Abstract

The New World Junonia butterflies include well-studied model organisms yet their phylogeny remains unresolved by traditional cox1 DNA barcodes. Sixteen Junonia mitochondrial genomes were sequenced using next generation MiSeq technology. Junonia lemonias, an Old World species, has mitochondrial genome features typical of Ditrysian Lepidoptera, and synteny is maintained throughout Junonia. Analysis of Junonia mitogenomes produced a robust phylogeny that was used with biogeographic information to infer that Junonia crossed the Pacific Ocean to invade the New World on 3 separate occasions. Junonia vestina, a high elevation species from the Andes Mountains, shows high altitude adaptation in the mitochondrial protein coding loci atp6, atp8, cox1, cob, nad1, and nad2, with the strongest effects seen in cox1 and nad1. There is some overlap between these genes with human loci that have disease associations with the same amino acid positions which could help elucidate the function of high elevation mutations in J. vestina.