High species richness of Northwest Pacific deep-sea amphipods revealed through DNA barcoding

• Published in: Progress in oceanography Vol. 178; p. 102184
• Main Authors: Jażdżewska, Anna Maria, Mamos, Tomasz
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.11.2019
• Subjects: Abyssal; Amphipoda; benthic organisms; DNA barcoding; gene flow; Hadal; Kuril-Kamchatka Trench; Molecular diversity; organic carbon; Species distribution; species richness; Hadal; DNA barcoding; Species distribution; Kuril-Kamchatka Trench; Abyssal; Molecular diversity; Amphipoda
• ISSN: 0079-6611; 1873-4472
• DOI: 10.1016/j.pocean.2019.102184

•Abyssal and hadal of Kuril-Kamchatka Trench area hosts diverse amphipod fauna.•Ca. half of the taxa were singletons. The distribution of taxa was species-specific.•Kuril-Kamchatka Trench does not constitute the barrier for some abyssal species.•The first comprehensive barcode reference library for abyssal Amphipoda is provided. Although deep sea has become a subject of intense studies in the recent years, our knowledge of the diversity of benthic organisms, especially at the molecular level, is far from complete. In the present study we focused on Amphipoda, known to be an abundant and diverse component of the marine zoobenthos. COI barcoding of an extensive collection of abyssal and hadal amphipods from the Kuril-Kamchatka Trench (KKT) area revealed 133 Molecular Operational Taxonomical Units (MOTUs). The richness of species varied between stations, with the highest observed in the areas where high organic carbon (Corg) content was recorded. Among the recognized MOTUs as many as 42% were singletons and only 28 were found at three or more stations. Their distribution was variable with seven taxa occurring at the most distant stations situated across the KKT. This shows that the trench does not constitute a barrier for the distribution of certain species. However, it may limit the gene flow in the case of others. The most common MOTUs were divided into three bathymetric categories: typically abyssal and hadal species as well as eurybathic ones inhabiting both the abyssal and hadal depth zones.