Panamanian Hoof Shell, Hipponix antiquatus

Panamanian Hoof Shell, Hipponix antiquatus. Shell provided by the commercial fishermen of the greater Los Cabos area, Baja California Sur, April 2009. Size: 2.5 cm (1.0 inch) x 1.1 cm (0.4 inches).

The Panamanian Hoof Shell, Hipponix panamensis (C.B. Adams, 1852, is a gastropod mollusk that is a member of the Hipponicidae Family of Hoofs, that is also known as the Pacific White Horse Hoof. The shell has a circular to oval outline. The apex is located close to the posterior margin and may overhang the margin. The apex is often heavily eroded in adult specimens. The exterior of the shell can vary from smooth to rough layered. They have a brown periostracum. The exterior of the shell is white, often with a light pink or brown wash. The interior is white and smooth. Panamanian Hoof Shells reach a maximum of 2.5 cm (1.0 inch) in length and 1.1 cm (0.4 inches) in height.

Panamanian Hoof Shells are found on, and under rocks, or attached to other shells. They live from the intertidal zone to depths up to 525 m (1,720 feet). They are found along the entire west coast of Mexico, including the Sea of Cortez.

Some sources consider Hipponix panamensis to be a synonym for Hipponix antiquatus, the Atlantic White Hoof, and not a stand alone species. The World Registry of Marine Species (WoRMS), however, currently lists Hipponyx panamensis as an accepted species and thus we have treated it accordingly.