San Diego Natural History Museum--Your Nature ConnectionSDNHM Biodiversity Research Center of the Californias - Marine Invertebrates

Souvenirs from the Sea



Estuaries include salt marshes and eel grass beds, among the most threatened of habitats. Invertebrate species that live in estuaries could also be in danger of disappearing if these habitats are not protected. Salt marsh species include the Mud Nassa and California Horn Snail, which live on mud flats, and the Coffee Bean snail, which lives in the Pickleweed marsh. The Pacific Bay Scallop occurs in the eel grass beds in shallow water. The Japanese Mussel is an introduced species that has infested bays of the west coast and forms dense mats on bay bottoms.

Salt Marsh Snail, photo by Scott Rugh  Pacific Calico Scallop, photo by Lollo Enstad Left: Salt Marsh Snail, Melampus olivaceus Carpenter, 1857 crawling on driftwood in pickleweed marsh, San Diego River
Right: Pacific Calico Scallop, Argopecten ventricosus (G.B. Sowerby II, 1842)


Soft-rock Reefs are the home of boring clams of at least a dozen species in several families. On top of these reefs may be found rocky shore species. Jewel Boxes are more common here than in other rocky areas. Illustrated are both species, the Reversed and Agate Jewel Boxes, attached to each other. These specimens washed up in Del Mar in February.

Flat-Tip Piddock, photo by Scott Rugh  Two species of Jewel Boxes attached to each other, photo by Scott Rugh
Left: Flat-Tip Piddock, Penitella penita (Conrad, 1837)
Right: two species of Jewel Boxes attached to each other; left is top view, right is side view. On top view, the species on the left is the Left-handed Jewel Box, Pseudochama exogyra (Conrad, 1837), and the red-colored species on the right is the Agate Jewel Box, Chama arcana (F.R. Bernard, 1976)

Kelp Forest and Ocean Surface Shells >>

Text by Scott Rugh, Collections Manager, Invertebrate Fossils; photos by Scott Rugh and Lollo Enstad