Identification Photos: Long-Spine Murex, Vokesimmunex tricoronis: The Long-Spine Murex has a moderately large, pale tan, club-shaped shell with fine red-brown spiral banding on its appendages and a porcelanous white interior.

The spire is moderately high, consisting of two and one-half nuclear whorls and seven or eight convex weakly shouldered post-nuclear whorls.

The aperture is moderately large and ovate. The siphonal canal is moderately long and narrowly open to the right.

The Long-Spine Murex is found on shallow water reefs up to 225 feet deep in the water column. It reaches a maximum size of 3.5 inches.

The Long-Spine Murex is rarely confused with other species from the Eastern Tropical Pacific Ocean.

In Mexican waters it has an extensive range, being found from Scammon’s Lagoon on the west coast of Baja California, south to Cabo San Lucas, throughout the Sea of Cortez, and south along the coast of the mainland to Guatemala.

The shells of the Long-Spine Murex provide homes to a variety of hermit crabs and are sold commercially to shell collectors. From a scientific perspective they have not been studied extensively.

The Long-Spine Murex is a member of the Muricidae Family, known as Rock Shells, a very large family, found worldwide, with approximately 100 genera and more than 700 species.

The shells vary in size from one-fourth inch to ten inches high. The shell may be elongated and broadly ovate to almost round. Some have long spines, others strong axial ribs, and some species are smooth. All have a stout, horny, oval operculum.

Murexes live on rocks or reefs and are carnivores, feeding on other gastropods as well as bivalves, barnacles, worms, coral, and other invertebrates. They attack their prey by boring holes, utilizing the radula and a gland in the foot that secretes various fluids to help in the boring action. The sexes are separate. The female lays the fertilized eggs in horny capsules, fastening them to rocks or hard objects singly or in clusters.

Long-Spine Murex, Vokesimmunex tricoronis: Collected by the commercial fishermen of the greater Los Cabos area of Baja California Sur, Mexico, September 2009. Size 6 cm (2.4 inches). Description and photos courtesy of John Snow.