Outer layer of the shell black, covered with an olive-green, or sometimes light bluish, epidermis; inside border black; a deep brown central spot. Distribution mainly southern, San Diego to Acapulco. A very beautiful color-pattern is shown. White rays alternate with dark olive.

Shell. Medium profile; apex positioned in anterior third of shell length. Anterior slope straight to convex; posterior and lateral slopes convex. Sculpture of imbricated primary and secondary radial riblets. Riblets equally developed on all surfaces. Color gray-green to orange; imbrications generally darker. Interior margin streaked or solid; intermediate area white; interior stain brown, irregular. Length, 10-50 mm. Animal. Black pigmentation on sides of foot, and dorsal surface of head. Radula. First lateral teeth closely set on anterior edge of ribbon segments, blunt distally. Second lateral teeth posterior and slightly lateral to first lateral teeth; broad, blunt distally. Third lateral teeth lateral to second lateral teeth; wedge-shaped, reduced. Uncini large. First lateral plates rectangular; second lateral plates irregular, posterior edge convex, separated from third lateral plates by complete suture. Third lateral plates lobate. Ventral plates rectangular.

Lottia limatula is represented in San Francisco Bay by a single specimen collected in early 1976. The specimen is over 25 mm in length and thus not recently settled. A form of Lottia limatula formerly referred to as Lottia limatula morchii Dall, 1878 is found in Tomales Bay, Marin Co., California. This form is characterized by an elevated shell which was thought to result from the estuarine conditions of Tomales Bay (McLean, 1966:75). Although the conditions at the locality in San Francisco Bay are similar to those in Tomales Bay, the specimen of Lottia limatula does not resemble Lottia limatula morchii form, but is identical to specimens of Lottia limatula from the open coast, particularly the Monterey Bay area. Lottia limatula is distinguished from all other species of the genus Lottia by the presence of imbrications on the radial riblets and the solid black pigmentation of the foot and head areas. See Remarks under Lottia scabra regarding earlier reports of this species from San Francisco Bay.

Newport, Oregon (44°N) to Isla Socorro, Revillagigedo Islands, Mexico (19°N) (McLean, 1966:74). San Francisco Bay: Marin County—Peninsula Point