Lithopoma americanum (Gmelin, 1791) American Starsnail
Distribution: Florida, Texas. Size: 25 to 38 mm.
Description: Color white to cream; shape conic and high; sculpture of thick, strong, wavy, knobby, irregular axial ribs; whorls thicker above and beneath incised suture; base of shell flattened with beaded spiral cords; ridge at base of columella; spire comes to a point; operculum typically thick, convex with a dimple.
Habitat: Shallow-water inhabitant of benthic areas; in hard and soft bottoms; under rocks and in grassy areas. Depth range 0 to 33 m (108 ft). Remarks: Primarily an epiphytic grazer on algae. Formerly called Astraea tecta americana. The related subspecies A. tecta tecta is larger and has stronger axial ribs that terminate as spines beyond the periphery of the shell. See Rehder (1981); Macia (2001). Synonym: A americanum (Gmelin, 1791).