Investigation of the Amathillopsidae (Amphipoda, Crustacea), including the description of a new species, reveals a clinging lifestyle in the deep sea worldwide.

Anne-Nina Lörz,Tammy Horton

doi:10.3897/zookeys.1031.62391

Abstract

Amathillopsidae is a widely distributed, but rarely sampled family of deep-sea amphipods. During a recent expedition to the North Atlantic, specimens were filmed clinging to a polychaete tube in situ at abyssal depths by a Remote Operated Vehicle and then sampled for further study. The species was new to science and is described in detail herein. A barcode sequence is provided. Further investigations of photographic and video records revealed the genus Amathillopsis to be more widely distributed, both geographically and bathymetrically, than indicated by current literature records, and that these species occur at abyssal depths in all oceans. Specimens of Amathillopsis are reported clinging to a variety of different organisms whose erect structures provide the means to raise these charismatic deep-sea predators above the seafloor facilitating feeding opportunities.

Highlights

During the third expedition of the Icelandic Genetics & Evolution (IceAGE) project on the RV ‘Sonne’ (Cruise SO267) to the North Atlantic from June to July 2020, large numbers of amphipod crustaceans were collected using a variety of methods
We have described a new species of Amathillopsis collected from abyssal depths and differentiated this new species from the known species found globally
A. grevei, A. roroi, and A. pacifica have been collected at abyssal depths; all other Amathillopsis species were collected shallower than 2000 m

Summary

Introduction

During the third expedition of the Icelandic Genetics & Evolution (IceAGE) project on the RV ‘Sonne’ (Cruise SO267) to the North Atlantic from June to July 2020, large numbers of amphipod crustaceans were collected using a variety of methods. A single specimen of the new species, collected at the Porcupine Abyssal Plain Sustained Observatory site at 4844 m, was found within the Discovery Collections at the National Oceanography Centre, Southampton, UK. The increased use of ROVs to capture high-resolution footage of deep-sea ecosystems has provided an opportunity for the study of poorly known and rarely captured organisms (Macreadie et al 2018). This is certainly the case with the Amathillopsidae. We provide collated records of ROV footage of a number of as yet unidentified species of Amathillopsis, from the deep sea, worldwide; confirming that despite the paucity of records and specimens, the genus is cosmopolitan and relatively common

Collection methods and locations

Taxonomic methods

Discussion