Maura False Limpet Shell, Siphonaria maura

Maura False Limpet Shell, Siphonaria maura. Shell collected off the beach at Punta Chivato, Baja California Sur, December 2025. Size: 2.0 cm (0.8 inches) x 15 cm (0.6 inches) x 8 cm (0.3 inches). Photographs and Identifications courtesy of Colin Campbell, DVM, Punta Chivato, Baja California Sur.

Maura False Limpet Shell, Siphonaria maura. Shells collected off the beach in the greater Los Cabos area, Baja California Sur, August 2021. Size: 2.0 cm (0.8 inches) x 1.6 cm (0.6 inches).

Phylogeny: The Maura False Limpet, Siphonaria maura (G.B. Sowerby, 1835), is a gastropod mollusk that is a member of the Siphonariidae Family of False Limpet Shells. The genus Siphonaria is one of four genera in this family, and there are one hundred forty-five species in this genus. Unlike true Limpets Maura False Limpets are pulmonate mollusks, meaning that they have traded their gills for primitive lung-type organs. The name Siphonaria comes from the Greek words that refer to the characteristic siphon (or tube) located on the right side of the animal, which connects the vascular cavity to the environment.  The species name maura is Latin and means “dark”. They are also known as the Dark False Limpet Shell.

Description: The Maura False Limpet Shell is ovate and varies in color, height and profile. The apex is located just below the shell’s center, and is often eroded. The exterior of the shell is sculpted with coarse and fine radial ribs. The exterior or the shell can be a light to very dark brown, often with white rays. The interior is brown to dark brown, with the white rays showing around the margin. Maura False Limpets reach a maximum of 2.2 cm (0.8 inches) in length and 1.8 cm (0.7 inches) in height.

Habitat and Distribution: Maura False Limpets are found attached to rocks in the intertidal zone. They are a subtropical to tropical Eastern Pacific species. They are found in all Mexican waters of the Pacific Ocean with the exception that they are absent from north of Magdalena Bay, Baja California Sur along the central and northwest coasts of the Baja Peninsula and north of La Paz, Baja California Sur, in the Gulf of California.

Ecology and Behavior: Maura False Limpets are grazers that feed primarily on micro algae. They are simultaneous hermaphrodites and reproduce sexually with indirect fertilization. The eggs are laid as a mass on the substrate. Their engagement in any type of commensal, parasitic, or symbiotic relationship has not been formally documented. From a conservation perspective they have not been formally evaluated. However, they are fairly common with a relatively wide distribution and should be considered to be of Least Concern.

Synonyms:  Siphonaria lecanium