First Records of a Rare Deep-sea Anglerfish, Himantolophus azurlucens, from the Western North Pacific, with Comments on the DNA Barcodes of the Genus (Lophiiformes: Himantolophidae)

Two specimens of a rare deep-sea anglerfish, Himantolophus azurlucens Beebe and Crane, 1947, were collected off the Pacific coast of northern Japan, representing the first records from the western North Pacific. These specimens represent the second and third records of the species since the original description, which was based on a single specimen from the eastern North Pacific; we determined that a previous record from the Atlantic was erroneous. We herein provide a description of the specimens and comments on intraspecific variation of the escal appendages. The new Japanese name “Masamori-chouchin-anko” is proposed for H. azurlucens . In addition, we provide DNA barcode sequences of the recently collected specimens of Himantolophus Reinhardt, 1837, including H. azurlucens and the fourth record of H. borealis Kharin, 1984, and demonstrate remarkably low intraspecific genetic variation of cytochrome c oxidase subunit I within the genus.