Nephelo Top Shell, Calliostoma nepheloide

Nephelo Top Shell, Cillistoma nepheloide.  Shell provided by the commercial fishermen of the greater Los Cabos area, Baja California Sur, August 2019. Size 2.5 cm (1.0 inch) x 2.6 cm (1.0 inch).

The Nephelo Top, Calliostoma nephaloide (Dall, 1913) is a gastropod mollusk that is a member of the Calliostomatidae Family of Noble Tops. The common name Nephelo comes from a Greek word meaning “cloudy”, the root word for nebula. The shells have an almost straight-sided cone shape, with the bottom whorl being slightly convex that is sculpted with finely beaded spiral strands. The exterior of the shell yellowish brown to olive brown in color, with darker markings. The Nephelo Top Shells reach a maximum of 2.8 cm (1.1 inches) in length and 2.9 cm (1.1 inches).

Nephelo Tops are found over and within mud substrate at depths between 73 m (240 feet) and 180 m (590 feet). They range from San Ignacio Lagoon, Baja California Sur to Panama; other than in the greater Cabo San Lucas area of Baja California Sur they are absent from the Sea of Cortez.