Red-colored Keyhole Limpet Shell, Fissurella rubropicta

Red-colored Keyhole Limpet Shell, Fissurella rubropicta. Shell collected off the beach in the greater San Diego area, San Diego, California, March 2014. Size: 2.5 cm (1.0 inch) x 1.4 cm (0.6 inches). Collection, photograph and identification courtesy Bob Hillis, Ivins, Utah.

Red-colored Keyhole Limpet, Fissurella rubropicta (Pilsbry, 1890), is a gastropod mollusk that is a member of the Fissurellidae Family of Keyhole Limpets. The shell has an oval fairly high profile with the exterior being sculpted with rough, radial ribs. The keyhole is set slightly forward of the shell’s center and the shells are wider in the center and narrower at both ends. The exterior of the shell has black and red ribs on a white background; the interior of mature shells is white with red or purple staining around the keyhole. Immature specimens are pale green, with red around the keyhole. The Red-colored Keyhole Limpets Shells reach a maximum length of 3.0 cm (1.2 inches) in length and 1.7 cm (0.7 inches) in height.

Red-colored Keyhole Limpets are found attached to rocks in the intertidal zone to depths up to 35 m (115 feet). They range from Cedros Island, Baja California to Costa Rica and are found throughout the Sea of Cortez.