Clanculus undatus (Lamarck, 1816)
Description: Shell large with rounded whorls; whorls and base bear beaded spiral ribs separated by faint oblique lamellae. Umbilicus open. Inner margin of outer lip irregularly toothed, aperture lirate. Columella coarsely toothed along its entire length. Colour brown with black spots on the spiral ribs, sometimes arranged into oblique lines. Interior iridescent.
Size: Up to 38 mm wide, 25 mm high.
Distribution: Endemic to Australia; Bega, NSW, to Rottnest Is, WA, including Tas.
Habitat: In South Australia, found under rocks on reefs on exposed coasts to about 15 m deep (Ludbrook, 1984). Known only from beach specimens in NSW. Uncommon.Figs. 1,2,3: Black River beach, near Stanley, Tasmania (C.100111)