LAUSR

The beluga whale Delphinapterus leucas (Mammalia: Cetacea: Monodontidae) is a small, toothed, Arctic and sub-Arctic cetacean threatened by human activities and environmental contamination. Herein, we report the first complete mitochondrial genome sequence of D. leucas, comprising 16,386 bp encoding the typical set of 37 mitochondrial genes, one replication origin, and a putative control region. It exhibits the classic vertebrate mitochondrial gene arrangement and demonstrated the highest similarity with the mitochondrial genome of the narwhal Monodon monoceros, a member of the only other extant genus in the Monodontidae family. Phylogenetic analysis using the 35 available Odontoceti (toothed whale) mitochondrial genomes clustered D. leucas with M. monoceros, with a tree topology that accorded well with traditional and recent molecular taxonomies. These data will provide information fundamental to conservation genetic studies of this endangered Arctic whale.