Bathymodiolus Kenk and Wilson, 1985

Saether, Kristian P., Little, Crispin T. S., Campbell, Kathleen A., Marshall, Bruce A., Collins, Mike & Alfaro, Andrea C., 2010, New fossil mussels (Bivalvia: Mytilidae) from Miocene hydrocarbon seep deposits, North Island, New Zealand, with general remarks on vent and seep mussels, Zootaxa 2577, pp. 1-45 : 14

Genus Bathymodiolus Kenk and Wilson, 1985

Bathymodiolus Kenk and Wilson, 1985: 255 . Type species (by original designation): Bathymodiolus thermophilus Kenk and Wilson, 1985 .

Discussion. The genus Bathymodiolus currently contains 22 described species, with one subspecies. As species were steadily added to the genus since its inception, and following the tentative placement of Bathymodiolus (s. l.) childressi by Gustafson et al. (1998), Cosel (2002) instigated an overhaul of the taxonomic status of the genus, dividing it into several groups based upon a number of shell and anatomical features. These features included the form of the posterior retractor, umbonal placement, and placement of the anterior retractor scar relative to the umbonal cavity. This study has since been bolstered by molecular analyses of the genus ( Miyazaki et al. 2004; Jones and Vrijenhoek 2006; Jones et al. 2006; Iwasaki et al. 2006; Samadi et al. 2007; Génio et al. 2008; Won et al. 2008; Fujita et al. 2009), confirming its paraphyletic status. Three clades are currently recognized within the genus Bathymodiolus , two within Bathymodiolus (s. l.) (the B. aduloides and B. childressi clades), and the B. thermophilus clade, or Bathymodiolus (s. s.) ( Cosel and Janssen 2008). The clades are themselves split into smaller groups based upon differences among the above-mentioned features plus consideration of shell size, shape, and form of the anterior margin ( Cosel and Janssen 2008). Several species currently referred to Bathymodiolus (s. l.) will probably eventually be referred to new genera (see also discussion of the genus Gigantidas below).