Family: Potamididae, Horn Shells view all from this family

Description 1-1 3/4" (2.5-4.4 cm) high. Moderately large, heavy; brown, with several white spiral bands. Whorls well-rounded, with many strong, rounded axial ribs crossed by weak spiral threads, and with several broad, yellowish axial varices. Aperture reddish, with a broad, expanded outer lip.

Habitat Intertidal mud flats in quiet bays and estuaries.

Range Bolinas Bay, California, to central Baja California.

Discussion Like other members of genus Cerithidea, large numbers of these shells may be encountered on exposed mud flats.