Noble Giant Turrid Shell, Polystira nobilis

Noble Giant Turrid Shell, Polystira nobilis. Shell provided by the commercial fishermen of the greater Los Cabos area, Baja California Sur, May 2014. Size: 5.7 cm (2.3 inches) x 2.0 cm (0.8 inches).

The Noble Giant Turrid, Polystira nobilis (Hinds, 1843), is a gastropod mollusk that is a member of the Turridae Family of Turrids. They are known in Mexico as pleurotoma noble. The shells consist of eight concave whorls and they are high spired, with a long open siphonal canal and a medium sized aperture. The shell is marked by spiral lines, following the whorls, with knobs along the shoulder. The exterior and interior of the shell are white with some specimens displaying brown blotching. Noble Giant Turrid Shells reach a maximum of 10.0 cm (3.9 inches) in length and 3.5 cm (1.4 inches) in height.

Noble Giant Turrids are found in muddy sand environments in at depths between 100 and 550 feet. They are similar to the Picta Turrid, Polystira picta, which has a narrower body. They are found throughout the Sea of Cortez, and range south to Panama; they have not been documented from the West Coast of Baja.

A synonym is Pleurotoma nobilis.