The Atlantic Equatorial Belt seep megafauna community structure is influenced primarily by depth rather than by geographic distance. The bivalves Bathymodiolinae (within Mytilidae) species or complexes of species are the most widespread in the Atlantic. The "Bathymodiolus boomerang" complex is found at the Florida escarpment site, the Blake Ridge diapir, the Barbados prism and the Regab site of Congo. The "Bathymodiolus childressi" complex is also widely distributed along the Atlantic Equatorial Belt from the Gulf of Mexico across to the Nigerian Margin, although not on the Regab or Blake ridge sites. The commensal polynoid, "Branchipolynoe seepensis" is known from the Gulf of Mexico, Gulf of Guinea and Barbados. Other species with distributions extending from the eastern to western Atlantic are: gastropod "Cordesia provannoides", the shrimp "Alvinocaris muricola", the galatheids "Munidopsis geyeri" and "Munidopsis livida" and probably the holothurid "Chiridota heheva".