Symbiotic associations between chemosynthetic bacteria and invertebrates are one of the major sources of primary production in deep-sea chemosynthesis-based ecosystems. Mussels of the genus Bathymodiolus (Bivalvia: Mytilidae) occur worldwide and can dominate the animal community at methane-rich cold seeps and sulfide-rich hydrothermal vents. Some species are associated with both sulfide-oxidizing and methanotrophic bacteria. These mussels are thus a good model for studying the diversity, role and ecology of multiple symbiotic associations, which are still poorly understood. For the present study, several species of mytilids were collected from seep and vent sites situated at depths from 850 to 3300 meters using submersibles. Symbiotic bacteria associated... |