Nut Cone Shell, Conus nux

Nut Cone Shell, Conus nux. Shell collected off the beach in the greater Los Cabos area, Baja California Sur, December 2010. Size: 1.5 cm (0.6 inches) x 1.0 cm (0.4 inches).

Nut Cone Shell, Conus nux. Shell collected off the beach at Punta Chivato, Baja California Sur, April 2022. Size: 1.7 cm (0.7 inches) x 1.2 cm (0.5 inches). Collection, photographs and Identification courtesy of Colin Campbell, DVM, Punta Chivato, Baja California Sur.

Nut Cone Shell, Conus nux. Shell collected off the beach at Punta Chivato, Baja California Sur, April 2022. Size: 1.9 cm (0.7 inches) x 1.2 cm (0.5 inches). Collection, photographs and Identification courtesy of Colin Campbell, DVM, Punta Chivato, Baja California Sur.

Phylogeny: The Nut Cone, Conus nux (Broderip, 1833), is a member of the Conidae Family of Cones. The genus Conus is one of eight genera in this family, and there are around eight hundred ten species in this genus. This species is also known as the Pigmy Cone. In Mexico they are called  Cono Nuez or Cono Pigmea.

Description: Nut Cones are small solid shells that have a cone-shaped outline. They have a low to moderate spire and a knobby top, leading to coronation on the shoulder. The aperture runs almost the entire length of the shell. The shell has a white exterior with irregular, brown or reddish-brown, banding and blotching. The  aperture is white with a purple tinge at the anterior end. Some individuals show purple banding inside the aperture. They are covered with a  thin  gray periostracum. The living animal is pink. Nut Cones are one of the smaller cones in the region, reaching a maximum of 2.6 cm (1.1 inches) in length and 1.6 cm (0.6 inches) in height.

Habitat and Distribution: Nut Cones are found in rock crevasses and under rock ledges. They live in the intertidal zone, and to depths up to 49 m (125 feet). They are a subtropical to tropical Eastern Pacific species. In Mexican waters they range from Magdalena Bay, Baja California Sur, to Guatemala,  including the entire Gulf of California and the Revillagigedo Islands.

Ecology and Behavior: Nut Cones are predators that feed primarily on marine worms. They are gonochoric and reproduce sexually, with external fertilization. There is no mention in the available literature of them engaging in any types of parasitic, commensal, or symbiotic relationships. Like all cone shells, this species is venomous and should be handled with extreme care, if at all. The venom from this shell contains chemicals that appear to be useful in treating malaria. This cone is one of the most common cones in the region. From a conservation perspective they are considered to be of Least Concern.

Synonyms: Conus pusillus and Harmoniconus nux.