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

Abstract

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.