A new abyssal amphipod species (Crustacea) from sunken wood described using integrative taxonomy. (March 2019) - Jażdżewska, Anna Maria
Highlights: A new species of amphipod genus Bathyceradocus was found in NW Pacific. It is the fourth wood-associated amphipod species collected at abyssal depths. The species exhibits high molecular diversity that may indicate the existence of stable population over long time. Abstract: During the expedition to the abyssal plain of Kuril-Kamchatka (KuramBio I) wood fragments were collected at seven stations. One of the wood-falls harboured a group of amphipods belonging to the genus Bathyceradocus known to be associated with this type of habitat. Morphological study of the collection revealed that the crustaceans belong to species new to science. The species presently described differs from known congeners in the armature of the mandibular palp, the shape of gnathopod 2, the shape of coxa 4 as well as the shape of the basis of pereopods 5–7. The studied collection consists of females (one ovigerous), two males and juveniles, so size-specific variation is also provided. It is the first record of Bathyceradocus in the Northwest Pacific and the fourth wood-associated amphipod species found in abyssal depths. Because the material was available for genetic study, cytochrome c oxidase I subunit (COI) sequences were analysed and six haplotypes were distinguished. There was relatively high intraspecific variation taking into account that all individuals came from a single station.