Odontoceti phylogeny and divergence data resolved: evidence from nuclear genes and complete mitochondrial genomes of Neophocaena phocaenoides

Odontoceti is a species suborder of cetaceans which are remarkable among mammals for most of them completely adapt to aquatic surroundings, some of them were listed on the convention on the conservation of migratory species of wild animals. Phylogenetic relationships within Odontoceti remains elusive. In this study, the complete mitochondrial genome of Finless Porpoise (Neophocaena phocaenoides) was firstly determined. The results of phylogenetic analyses supported Ziphius and Delphinida clustered in a clade, and the clade and Physeter formed a sister relationship. In the Delphinida, Phocoenidae and Mondontidae gathered into a clade, subsequently they and Delphinidae constituted a sister taxa, which was also supported with strong Bayesian posterior probability. In addition, the analysis of divergence dates suggested that the main Odontocete lineages diversified in Oligocene and Miocene and confirmed that Delphinoidea originated in the Early Miocene. The divergence time of Phocoena phocaenoides and N. phocaenoides occurred in Late Miocene.