Symbiont Community Composition in Rimicaris kairei Shrimps from Indian Ocean Vents with Notes on Mineralogy

Abstract

Hydrothermal vent shrimps in the genus Rimicaris are among the most charismatic deep-sea animals of Atlantic and Indian Oceans, often occurring on towering black smokers in dense aggregates of thousands of individuals. Although this dominance is only possible because of symbiosis, no study on the symbiosis of Indian Ocean Rimicaris species has been conducted.

Symbioses of alvinocaridid shrimps from the South West Pacific: No chemosymbiotic diets but partially conserved gut microbiomes

“…A slightly more developed colonization was observed on their mouthparts with some filamentous bacteria although limited to particular areas, mostly the plumose setae on the mouthpart margins. This sharply contrasts with colonization patterns seen not only in alvinocaridid species relying mostly on their cephalothoracic chemosymbiosis such as Rimicaris exoculata (Zbinden et al ., 2004; Petersen et al ., 2010; Zbinden and Cambon-Bonavita, 2020) or Rimicaris kairei (Methou, Hikosaka, et al ., 2022), but also in those with a mixed diet, only partially dependent on this symbiosis like Rimicaris chacei (Apremont et al ., 2018), and which all exhibit extensive colonization of their cephalothoracic cavities by filamentous bacteria. Although earlier works stress out the importance of the moult cycle in R. exoculata symbiosis (Corbari et al ., 2008), with a sparse colonization within the cephalothoracic cavity in early moult stage individuals, it is unlikely that moult stages have introduced a bias in our observations for alvinocaridids from South West pacific basins.…”

“…Although bacterial coverage on mouthparts of R. variabilis , N. saintlaurentae and Manuscaris sp. was very low comparatively to Rimicaris species from the Atlantic or Indian Oceans, the composition of their epibiotic communities mirrors those previously observed in cephalothoracic cavities of the latter (Zbinden et al ., 2008; Petersen et al ., 2010; Guri et al ., 2012; Jan et al ., 2014; Apremont et al ., 2018; Cambon-Bonavita et al ., 2021; Methou, Hikosaka, et al ., 2022). Thus, we found a similar phylogenetic diversity with a dominance of Campylobacterota , followed by several families of Proteobacteria - including α- , γ- and ζ-proteobacteria - as well as Bacteroidota epibionts.…”

“…These shrimps host a complex community of cocci, rod-shaped and filamentous epibionts on the inner side of their enlarged cephalothorax, i.e. the branchiostegite, and on setae covering the surface of their hypertrophied mouthparts (Zbinden et al ., 2004; Petersen et al ., 2010; Methou, Hikosaka, et al ., 2022). These communities comprise a wide diversity of chemosynthetic partners including Campylobacterota , α- , γ- and ζ-Proteobacteria as well as Desulfobacterota among others (Zbinden et al ., 2008; Petersen et al ., 2010; Guri et al ., 2012; Jan et al ., 2014; Jiang et al ., 2020; Cambon-Bonavita et al ., 2021; Methou, Hikosaka, et al ., 2022), from which their hosts derive most of their nutrition (Polz et al ., 1998; Gebruk et al ., 2000; Van Dover, 2002; Methou et al ., 2020) through direct transtegumental transfer of organic compounds (Ponsard et al ., 2013).…”

“…the branchiostegite, and on setae covering the surface of their hypertrophied mouthparts (Zbinden et al ., 2004; Petersen et al ., 2010; Methou, Hikosaka, et al ., 2022). These communities comprise a wide diversity of chemosynthetic partners including Campylobacterota , α- , γ- and ζ-Proteobacteria as well as Desulfobacterota among others (Zbinden et al ., 2008; Petersen et al ., 2010; Guri et al ., 2012; Jan et al ., 2014; Jiang et al ., 2020; Cambon-Bonavita et al ., 2021; Methou, Hikosaka, et al ., 2022), from which their hosts derive most of their nutrition (Polz et al ., 1998; Gebruk et al ., 2000; Van Dover, 2002; Methou et al ., 2020) through direct transtegumental transfer of organic compounds (Ponsard et al ., 2013). This diversity of bacterial partners reflects a diversity of metabolisms based on a wide range of energy sources (Jan et al ., 2014; Jiang et al ., 2020; Cambon-Bonavita et al ., 2021) enabling these animals to thrive in vent fields with contrasting profiles of fluid chemistries.…”

Symbioses of alvinocaridid shrimps from the South West Pacific: No chemosymbiotic diets but conserved gut microbiomes

“…Among them, Rimicaris exoculata and Rimicaris kairei form large aggregations of thousands of individuals, gathered in the close vicinity of fluid emissions respectively in the Mid Atlantic Ridge and the Central Indian Ridge (Zbinden & Cambon‐Bonavita, 2020). These shrimps host a complex community of cocci, rod‐shaped and filamentous epibionts on the inner side of their enlarged cephalothorax, that is, the branchiostegite, and on setae covering the surface of their hypertrophied mouthparts (Methou et al, 2022b; Petersen et al, 2010; Zbinden et al, 2004). These communities comprise a wide diversity of chemosynthetic partners including Campylobacterota , α‐ , γ‐ and ζ‐Proteobacteria as well as Desulfobacterota among others (Cambon‐Bonavita et al, 2021; Guri et al, 2012; Jan et al, 2014; Jiang et al, 2020; Methou et al, 2022b; Petersen et al, 2010; Zbinden et al, 2008), from which their hosts derive most of their nutrition (Gebruk et al, 2000; Methou et al, 2020; Polz et al, 1998; Van Dover, 2002) through direct transtegumental transfer of organic compounds (Ponsard et al, 2013).…”