Toggle Main Menu Toggle Search

Open Access padlockePrints

The Multi-Ocean Distribution of the Hadal Amphipod, Hirondellea dubia Dahl, 1959 (Crustacea, Amphipoda)

Lookup NU author(s): Dr Johanna Weston, Dr Alan Jamieson



This work is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).


Copyright © 2022 Weston and Jamieson.The hadal zone (depths > 6,000 m) comprises isolated features that host high degrees of endemism, with species inhabiting only a single feature or a group of adjacent features. The amphipod, Hirondellea dubia is an abundant scavenger at the hadal depths of the Kermadec, Tonga, and New Hebrides trenches in the Southwest Pacific Ocean, particularly at depths > 9,500 m. However, several records have hinted that H. dubia may not be restricted to the Southwest Pacific nor be exclusively hadal. Here, we present new records of H. dubia recovered by baited landers deployed to five hadal trenches during three expeditions and assess the geographic and vertical distribution of this species. To rule out the possibility of cryptic diversity, morphological taxonomy was paired with two mitochondrial markers (16S and COI) to test for species boundaries among the new and published molecular data using four delineation approaches (ABGD, CD-HIT, GMYC, and bPTP). We found H. dubia to be a single species and not restricted to the Southwest Pacific or hadal depths. This species’ geographic range extends from the Southwest Pacific to the Mariana Trench (Northwest Pacific), the Clarion-Clipperton Zone (Central Pacific), the South Sandwich Trench (Southern), and the Puerto Rico Trench (North Atlantic). This amphipod’s vertical range spans over half of the ocean’s total depth, between 4,700 and 10,817 m. This study presents an extraordinary geographic range extension to a species long considered endemic to a cluster of three Southwest Pacific trenches and shows a pan-oceanic distribution across extremely isolated hadal features.

Publication metadata

Author(s): Weston JNJ, Jamieson AJ

Publication type: Article

Publication status: Published

Journal: Frontiers in Marine Science

Year: 2022

Volume: 9

Online publication date: 04/03/2022

Acceptance date: 27/01/2022

Date deposited: 19/04/2022

ISSN (electronic): 2296-7745

Publisher: Frontiers Media S.A.


DOI: 10.3389/fmars.2022.824640


Altmetrics provided by Altmetric


Funder referenceFunder name
Newcastle University Research Infrastructure Fund
Schmidt Ocean Institute
Victor Vescovo of Caladan Oceanic LLC