Widespread mitochondrial DNA haplotypes ofPteroptyxspp. across present–day river systems in Southeast Asia and their historical dispersal through ancient river networks

Abstract

ABSTRACTEstuarine fireflies from the genusPteroptyxare widely distributed in Southeast Asia and famous for their nightly displays of bioluminescence by adult fireflies congregating or lekking on mangrove trees.Pteroptyxfireflies also offer insights into the history of the region, as their distribution in many of the isolated rivers they now inhabit are likely a product of dispersal via palaeorivers that formed in Southeast Asia during the Pleistocene. Here, we report the presence of widespread cytochrome oxidase subunit I (cox1) haplotypes among populations ofPteroptyxspp. in estuaries throughout Southeast Asia and suggest possible dispersal routes for these haplotypes vis-à-vis the Siam and Malacca River systems. Separately, reconstruction of the haplotype tree from thecox1gene indicated that the ancestors ofPteroptyx asymmetria, Pteroptyx bearni, Pteroptyx malaccae, Pteroptyx tener, andPteroptyx validaeither had a Thai, Bornean, or Peninsular Malaysian origin. Previous reconstructions of the phylogenetic and network trees ofPteroptyxsp. did not consider the presence of identical mitochondrial DNA haplotypes in their datasets, and the role palaeorivers had on their dispersal. The perspectives reported here aim to guide future taxonomic, phylogenetic and phylogeographic work onPteroptyxfireflies in Southeast Asia.