Striped Limpet Shell, Lottia fascicularis

Striped Limpet Shell, Lottia fascicularis. Shell collected off the beach in the greater Los Cabos area, Baja California Sur, January 2020. Size: 3.0 cm (1.2 inches) x 2.3 cm (0.9 inches).

Phylogeny: Striped Limpets, Lottia fascicularis (Menke, 1851) are gastropod mollusks in the Lottiidae Family of True Limpet Shells, and the subfamily Lottinae, and the tribe Lottini. The genus Lottia is one of four genera in the Lottini Tribe. The Lottia Genus contains sixty-four species. The genus name Lottia seems to stem from the Latin word Lotharius, meaning “famous warrior.” This name possibly refers to the shield-like structure of limpet shells. The species name fasicularis comes from the Latin word meaning “striped”, “banded”, or “bundled.” They are known in Mexico as Lapa a Rayas.

Description:  Striped Limpet Shells have an oval profile and are only moderately elevated. The exterior of the shell is sculpted with very fine radial ribbing. The apex is often eroded. These shells are variable in coloration and markings. They may be white of reddish-brown in color. Most are marked with dark gray or dark brown fine radial lines. The lines may be straight, curvy, forked, or intermittent. The apex may be solid brown. Generally, the lines continue to the margin, but not always. Some species have tan maculations near the lines. The interior is white, with brown staining in the center. Southern populations often lack the lines and are solid reddish-brown or white. They reach a maximum of 3.0 cm (1.2 inches) in length.

Habitat and Distribution: Striped Limpets are found attached to rocks in the intertidal zone. They are a subtropical to tropical Eastern Pacific species that are found in all Mexican waters of the Pacific Ocean with the exception that they are absent from north of Bahía San Carlos, Sonora and north of El Conejo, Baja California Sur, along the central and northwest coasts of the Baja Peninsula.

Ecology and Behavior: Striped Limpet are grazers that consume algae and diatoms, which they scrape from the rock with their radula. In turn they are preyed upon by shorebirds, crabs, fish and sea stars. They are gonochoric and reproduce sexually, through broadcast spawning, with external fertilization. From a conservation perspective the Striped Limpet Shell has not been formally evaluated, however, they are fairly common with a relatively wide distribution and should be considered to be of Least Concern.

Synonyms: Acmaea fascicularis, Nomaeopelta myrae, Notoacmea fascicularis, and Patella opea.