Caecum clava Folin, 1867 Blade Caecum
Distribution: Texas; West Indies. Size: 2 to 3 mm
Description: Color glossy white; shape toothlike or tusklike, slender, not as arched as most members of Caecum; sculpture of prominent longitudinal ribs that slightly wind around the tube of the shell extending from mucro to apertural lip, where microscopic radial striae can be seen between the ribs; mucro flat and triangular; aperture round and bulbous.
Habitat: Primarily in mud shale domes of Stetson Bank and also at Seven and One-half Fathom Reef. Depth range from 0 to 101 m (330 ft). Remarks: The thickened aperture may act as an anchor in the soft, muddy environments to prevent the snail from sinking too deeply into the substrate. See Tunnell and Chaney (1970); Ode (1988b); Hyde (2000).