Phylogenetic relationships of three representative sea krait species (genus <i>Laticauda</i>; elapidae; serpentes) based on 13 mitochondrial genes

<p>To investigate the phylogenetic relationships of the genus <i>Laticauda</i> to related higher taxa, we compared the sequences of four mitochondrial genes (12S rRNA, 16S rRNA, ND4, Cyt<i>b</i>) from three <i>Laticauda</i> species (<i>L. colubrina</i>, <i>L</i>. <i>laticaudata</i>, and <i>L</i>. <i>semifasciata</i>) with those of 55 Asian and Australo-Melanesian elapid species. We also characterized the complete mitogenomes of the three <i>Laticauda</i> species and compared the sequences of 13 mitochondrial genes from <i>Laticauda</i> species with five terrestrial elapid and one viperid species to estimate phylogenetic relationships and divergence times. Our results showed that the genus <i>Laticauda</i> is paraphyletic to terrestrial elapids and diverged from the Asian elapids approximately 16.23 Mya. The mitogenomes of the three <i>Laticauda</i> species commonly encoded 13 proteins, 22 tRNAs, 12S and 16S rRNAs and two control regions and ranged from 17,170 and 17,450 bp in size. The <i>L. colubrina</i> mitogenome was more similar to that of <i>L. laticaudata</i> than that of <i>L. semifasciata</i>. The divergence time among the three <i>Laticauda</i> clades was estimated at 8–10 Mya, and a close phylogenetic relationship between <i>L. colubrina</i> and <i>L. laticaudata</i> was found. Our results contribute to our understanding of the evolutionary history of sea kraits.</p>