Webbed Murex Shell, Purpurellus pinniger

Webbed Murex Shell, Purpurellus pinniger. Shell collected off the beach of Punta Chivato, Baja California Sur, May 2023. Size: 6.5 cm (2.5 inches) x 3.1 cm (1.2 inches).  Collection and photographs courtesy of Colin Campbell, DVM, Punta Chivato. Identification courtesy of Dr. Hank Chaney, Santa Barbara Museum of Natural History, Santa Barbara, California.

Webbed Murex Shell, Purpurellus pinniger.  Shell snagged with yo-yo iron out of 100-foot water off Point Palmilla, Baja California Sur, May 2021. Size: 6.3 cm (2.5 inches) x 3.6 cm (1.4 inches).

Webbed Murex Shell, Purpurellus pinniger. Shell collected off the beach of Punta Chivato, Baja California Sur, May 2023. Size: 5.6 cm (2.2 inches) x 2.8 cm (1.1 inches). Collection and photographs courtesy of Colin Campbell, DVM, Punta Chivato.  Identification courtesy of Dr. Hank Chaney, Santa Barbara Museum of Natural History, Santa Barbara, California.

Phylogeny: The Webbed Murex Shell, Purpurellus pinniger (Broderip, 1833), is a gastropod mollusk that is a member of the Muricidae Family of Rock Shells. The genus Purpurellus is one of one hundred ninety-eight genera in this family, and there are three species in this genus. They are  also known as the Pinniger Murex Shell and in Mexico as as Murex Palmeado.

Description: Webbed Murex Shells are medium-sized murexes that consist of around four or five whorls. They derive their common name from the webbed fronds, or wings, that comprise the varices. The outside edges of the varices are wavy. They are triangular in cross-section with three similar sized sides. The aperture is oval shaped. The canal is closed most of its length and widens as a frond towards its end. These beautiful shells may be whitish, pink, lavender, or all three colors, with varying numbers of brown bands. Webbed Murex Shells reach a maximum of 8.5 cm (3.3 inches) in length and 4.9 cm (1.9 inches) in height.

Habitat and Distribution: Webbed Murexs are found in rubble, on rocks, and occasionally, on sand, at depths of 11 m (36 feet) to 82 m (270 feet). 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 the west coast of the Baja Peninsula and north of Bahía de Los Ángeles, Baja California, in the Sea of Cortez.

Ecology and Behavior: Webbed Murexs are a poorly studied and understood species. Their diet, predation, reproduction or ecosystem interactions has not been documented. Other species in the Muricidae Family are predators that feed primarily on barnacles, bivalves, and  gastropods. They are gonochoric and reproduce sexually, with internal fertilization. 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 consider to be of Least Concern. These shells are highly sought after by collectors.

Synonyms: Centrifuga inezana, Murex cristatus, Murex osseus, Murex pinniger, and Pterynotus pinniger.