Different energy sources for three symbiont-dependent bivalve molluscs at the Logatchev hydrothermal site (Mid-Atlantic Ridge)

• Published in: Journal of the Marine Biological Association of the United Kingdom Vol. 81; no. 4; pp. 655 - 661
• Main Authors: Southward, Eve C., Gebruk, Andrey, Kennedy, Hilary, Southward, Alan J., Chevaldonné, Pierre
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 01.08.2001
• Subjects: Bathymodiolus puteoserpentis; Bivalvia; Calyptogena; Carbon; Energy resources; Energy sources; Laboratories; Marine; Microscopy; Mollusks; Nitrogen; Research Article; Sediments; Stable isotopes; Thyasiridae; United Kingdom > UK; Mid-Atlantic Ridge; AN, Mid-Atlantic Ridge; A, Mid-Atlantic Ridge
• ISSN: 0025-3154; 1469-7769
• DOI: 10.1017/S0025315401004337

The vent mussel Bathymodiolus puteoserpentis, a large vesicomyid clam and a smaller thyasirid were collected from an area of sediment subject to diffuse hydrothermal flow. The mussels live on the surface, the vesicomyids are partly buried and the thyasirids burrow in the sediment. The fine structure of the gills differs in the three bivalves. Bathymodiolus puteoserpentis hosts two types of bacterial symbiont, one methanotrophic, and another probably thiotrophic. The other two bivalves have single types of symbiont of different shapes. Stable isotope ratios of carbon and nitrogen indicate thiotrophy in the vesicomyid and thyasirid, but a predominance of methanotrophy in the mussel. This is the first time that such an assemblage has been found at a hydrothermal site on the Mid-Atlantic Ridge (MAR), with the different faunistic elements exploiting different energy resources.