Inter- specific and subspecific genetic divergences of freshwater eels, genus Anguilla including a recently described species, A. luzonensis, based on whole mitochondrial genome sequences

We examined general characteristics and genetic divergences of whole mitochondrial genome sequences for all 19 species/subspecies of the genus Anguilla including a recently described new species, A. luzonensis. The entire genome ranged from 16,550 (A. borneensis) to 16,833 base pairs (A. nebulosa labiata), and general characteristics such as length of each gene and gene order were very conservative across the genus and also similar with other anguilliform and bony fishes. Pairwise comparisons of sequence differences showed that interspecific divergences did not overlap with intersubspecific variations and found a clear hierarchical structure in the genus Anguilla, in which the two subspecies of A. australis and A. nebulosa had slight and the smallest differences among all species/subspecies pairs, followed by the two subspecies of A. bicolor, the A. anguilla and A. rostrata pair, and the other species pairs in order. A. luzonensis showed considerable sequence differences from all other species in all genes and was appeared to be genetically close to A. interioris. The present study analyzed the whole mitochondrial genome of A. luzonensis for the first time and genetic divergences for all anguillid species and subspecies, and provided basic information for revision and reaching agreement about the taxonomy of the genus Anguilla using molecular characteristics, which have been discussed recently