Linking regional variation of epibiotic bacterial diversity and trophic ecology in a new species of Kiwaidae (Decapoda, Anomura) from East Scotia Ridge (Antarctica) hydrothermal vents

• Published in: MicrobiologyOpen
• Main Authors: Zwirglmaier, Katrin, Reid, William, Heywood, Jane, Sweeting, Christopher, Wigham, Benjamin, Polunin, Nicholas, Hawkes, Jeffrey, Connelly, Douglas, Pearce, David, Linse, Katrin
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley-Blackwell 2015
• Subjects: C500 Microbiology; F700 Ocean Sciences; Calvin; East Scotia Ridge; Southern Ocean; Antarc*; Antarctica
• Online Access: https://nrl.northumbria.ac.uk/id/eprint/21216/; https://doi.org/10.1002/mbo3.227; https://nrl.northumbria.ac.uk/id/eprint/21216/1/mbo3227.pdf

We analyzed the diversity of bacterial epibionts and trophic ecology of a new species of Kiwa yeti crab discovered at two hydrothermal vent fields (E2 and E9) on the East Scotia Ridge (ESR) in the Southern Ocean using a combination of 454 pyrosequencing, Sanger sequencing, and stable isotope analysis. The Kiwa epibiont communities were dominated by Epsilon- and Gammaproteobacteria. About 454 sequencing of the epibionts on 15 individual Kiwa specimen revealed large regional differences between the two hydrothermal vent fields: at E2, the bacterial community on the Kiwa ventral setae was dominated (up to 75%) by Gammaproteobacteria, whereas at E9 Epsilonproteobacteria dominated (up to 98%). Carbon stable isotope analysis of both Kiwa and the bacterial epibionts also showed distinct differences between E2 and E9 in mean and variability. Both stable isotope and sequence data suggest a dominance of different carbon fixation pathways of the epibiont communities at the two vent fields. At E2, epibionts were putatively fixing carbon via the Calvin-Benson-Bassham and reverse tricarboxylic acid cycle, while at E9 the reverse tricarboxylic acid cycle dominated. Co-varying epibiont diversity and isotope values at E2 and E9 also present further support for the hypothesis that epibionts serve as a food source for Kiwa.