Obelisk Murex Shell, Dermomurex obeliscus

Obelisk Murex Shell, Dermomurex obeliscus. Shell provided by the commericial fishermen of the greater Los Cabos area, Baja California Sur, March 2014. Size: 2.3 cm (0.9 inches) x 1.0 cm (0.4 inches).

The Obelisk Murex, Dermomurex obeliscus (Adams, 1853), is a gastropod mollusk that is a member of the Muricidae Family of Rocks, with the name derived from their somewhat straight sides, rising to a pyramidal top. These shells always appear to be worm and eroded and have five to six whorls and a tall blunt spire, low and rounded varices and a relatively small short, curved, open siphon. The exterior of the shell is white to light tan, with numerous, narrow, reddish-brown, spiral lines. Obelisk Murex Shells reach a maximum of 3.3 cm (1.3 inches) in length and 1.4 cm (0.6 inches) in height.

The Obelish Murexs have a known range from Mazatlán, Sinaloa to Costa Rica. The shell photographed below was collected in the greater Todos Santos area of Baja California Sur indicative that it is a resident of the coastal waters of Baja.

A synonym is Murex obeliscus.