Population structure of the mussel “ Bathymodiolus” childressi from Gulf of Mexico hydrocarbon seeps

Hydrocarbon and brine seeps in the deep regions of the northern and western Gulf of Mexico often support populations of the bathymodiolin mussel, “ Bathymodiolus” childressi. In this study, we use two mitochondrial and six nuclear DNA markers to investigate relationships within the metapopulation of “ B.” childressi in the Gulf of Mexico from Mississippi Canyon to Alaminos Canyon over a range of 527–2222 m in depth and approximately 550 km in distance. Restriction fragment length polymorphism (RFLP) and size polymorphism analysis of the markers suggest that populations are not genetically differentiated. F ST values were not significantly different from zero. The presence of a panmictic population of “ B.” childressi over such a broad range of depth suggests that this species may be quite different from most members of the Gulf of Mexico seep chemosynthetic communities.