A Hidden Diversity in the Atlantic and the SE Pacific: Hamatipedidae n. fam. (Crustacea: Tanaidacea)

Marta Gellert,Graham Bird,Magdalena Błażewicz,Anna Stȩpień,Maciej Studzian

doi:10.3389/fmars.2021.773437

Abstract

A new family of paratanaoidean Tanaidacea, the hamatipedids, formerly part of the Typhlotanaidae, is established to accommodate three genera (Hamatipedaand two new). Deep-sea hamatipedids collected from four sites in the Atlantic (Argentine and Guiana basins) and 14 sites from the Southeast coast of Australia were studied using a taxonomic approach combining morphological and morphometric data. Four new species ofHamatipedaand one of a new genus are described from different deep-sea areas of the Atlantic and Pacific oceans.Hamatipeda simaoriginally classified withinHamatipeda, is transferred to a new genus. We observed that several morphometric characters (i.e., length of the last two pereonites) in different life-stages of one of the newHamatipedaspecies (neuter, manca-2, and manca-3) are correlated with the total body length (TBL). Applying a morphometric approach, we aimed: (1) to identify those ontogenetic-dependent characters, and (2) to detect the characters, which can be used in discrimination of Hamatipedidae species, regardless their life-stage.

Highlights

Intensive exploration of the deep sea since the 1960s has uncovered a remarkable diversity of benthic organisms (Sanders et al, 1965; Sanders, 1968)
Except for Yarutanais sima that occurs in the shallow Bass Strait, all hamatipedids inhabit greater depths beyond the continental shelf, i.e., on the continental slope and only two are known from the abyssal
The proposed new family is the twentieth recent family of the Paratanaoidea and the eleventh that apparently radiated in lightdeprived environments such as the deep-sea

Summary

Introduction

Intensive exploration of the deep sea since the 1960s has uncovered a remarkable diversity of benthic organisms (Sanders et al, 1965; Sanders, 1968). A paucity of specialists and awareness of the role taxonomy for understanding and protection of the biodiversity has meant that collections of invertebrates from deep-sea expeditions were shelved in museums awaiting the attention of taxonomists and formal description (Brandt et al, 2007; Appeltans et al, 2012). Among these organisms is the superfamily Paratanaoidea Lang, 1949, a monophyletic group of the crustacean suborder Tanaidomorpha (Kakui et al, 2011).

Methods

Results

Conclusion