New records of Leptacanthichthys gracilispinis and Microlophichthys microlophus (Actinopterygii: Lophiiformes: Oneirodidae) from the subarctic Atlantic Ocean, including new lophiiform barcoding data and a rare observation of a copepod parasite in ceratioid anglerfishes

Abstract

In an ongoing effort to document and/or validate taxonomic identifications and monitor fishes in the subarctic Atlantic Oceans, including the production of pragmatic identification material, two new distributional records of ceratioid anglerfishes are presented: Leptacanthichthys gracilispinis (Regan, 1925) and Microlophichthys microlophus (Regan, 1925) of the dreamer family Oneirodidae. The former belongs to the relatively rarely observed “long-pectoraled” subgroup whereas the latter is a relatively common species distributed circumglobally in temperate and tropical waters. Both species were recorded for the first time off Greenland and the specimens could be expatriates although the diversity of deep-sea pelagic fishes in the subarctic Atlantic Ocean is not well known. In addition, molecular barcoding Cox1 DNA sequences of subarctic Atlantic lophiiform taxa are included, where the material was available, many being produced as part of the Greenland fishes barcoding program, a continuous effort to register and barcode all Greenland fish species. The program has currently barcoded 220 taxa of approximately 300 known fish species observed in Greenland waters, with the ceratioid anglerfishes constituting one of the most problematic fish groups in the region in terms of sampling, identification, and taxonomic assignments using integrative taxonomy. Taxonomic issues based on molecular OTUs* are reported for the genera Caulophryne, Cryptopsaras, and Dolopichthys based on Cox1 data. Finally, a relatively large copepod parasite in the family Pennellidae was found on L. gracilispinis and constitutes one of only two copepod parasites recorded on ceratioid anglerfishes.

Keywords

• Ceratioidei
• Greenland fishes
• Monitoring of subar