Ancistrobasis
Ancistrobasis is a genus of sea snails, marine gastropod mollusks in the family Seguenziidae. Dall (1889) regarded (with some doubt) "Ancistrobasis" as a section of the closely related genus "Basilissa" "Watson, 1879". Description. This genus contains the dentate forms of species formerly included in the genus "Basilissa". Shell: The conical shell shows peripheral carina and collabral axial riblets. The midwhorl angulation and the spiral lirae are present on all whorls. The posterior sinus depth is shallow. The posterior sinus has an U-shape. The anterolateral sinus is absent. The rhomboidal aperture contains a basal and columellar sinus. The umbilical  septum (a transverse plate secreted with early formed whorls of the shell) is absent. The shell contains pustulate microsculpture. Radula: The rachidian tooth is broader than high with lateral wings prominent. The lateral tooth cusp is broad. The radula contains less than 10 marginal tooth pairs. Species. Species within the genus "Ancistrobasis" include: