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Integrative taxonomy revisits the ontogeny and trophic niches of Rimicaris vent shrimps.

ABSTRACT: Among hydrothermal vent species, Rimicaris exoculata is one of the most emblematic, hosting abundant and diverse ectosymbioses that provide most of its nutrition. Rimicaris exoculata co-occurs in dense aggregates with the much less abundant Rimicaris chacei in many Mid-Atlantic Ridge vent fields. This second shrimp also houses ectosymbiotic microorganisms but has a mixotrophic diet. Recent observations have suggested potential misidentifications between these species at their juvenile stages, which could have led to misinterpretations of their early-life ecology. Here, we confirm erroneous identification of the earliest stages and propose a new set of morphological characters unambiguously identifying juveniles of each species. On the basis of this reassessment, combined use of C, N and S stable isotope ratios reveals distinct ontogenic trophic niche shifts in both species, from photosynthesis-based nutrition before settlement, towards a chemosynthetic diet afterwards. Furthermore, isotopic compositions in the earliest juvenile stages suggest differences in larval histories. Each species thus exhibits specific early-life strategies that would, without our re-examination, have been interpreted as ontogenetic variations. Overall, our results provide a good illustration of the identification issues persisting in deep-sea ecosystems and the importance of integrative taxonomy in providing an accurate view of fundamental aspects of the biology and ecology of species inhabiting these environments.

SUBMITTER: Methou P

PROVIDER: S-EPMC7428246 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Integrative taxonomy revisits the ontogeny and trophic niches of Rimicaris vent shrimps.

Methou Pierre P Michel Loïc N LN Segonzac Michel M Cambon-Bonavita Marie-Anne MA Pradillon Florence F

Royal Society open science 20200708 7

Among hydrothermal vent species, Rimicaris exoculata is one of the most emblematic, hosting abundant and diverse ectosymbioses that provide most of its nutrition. Rimicaris exoculata co-occurs in dense aggregates with the much less abundant Rimicaris chacei in many Mid-Atlantic Ridge vent fields. This second shrimp also houses ectosymbiotic microorganisms but has a mixotrophic diet. Recent observations have suggested potential misidentifications between these species at thei ...[more]

PMID: 32874664

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Dataset Information

Integrative taxonomy revisits the ontogeny and trophic niches of Rimicaris vent shrimps.

Publications

Integrative taxonomy revisits the ontogeny and trophic niches of <i>Rimicaris</i> vent shrimps.

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