Channeled Sea Star, Tethyaster canaliculatus

Channeled Sea Star, Tethyaster canaliculatus. Sea Star provided by the commercial fishermen of the greater Los Cabos area, Baja California Sur, November 2011. Pictured star wingspan: 16 cm (6.3 inches).

Phylogeny: The Channeled Sea Star, Tethyaster canaliculatus (A. H. Clark, 1916), is a member of the Astropectinidae Family of Starfish and is known in Mexico as estrella acanalada. The Tethyaster Genus has ten known global species.

Morphology:  Channeled Sea Star have a somewhat flattened, with a wide central disc and five narrow, tapering arms that often differ in lengths. These tube feet do not have suckers. The plates along the margins of the arms are very obvious. These stars may be mottled or solid colored with brown, orange, reddish-brown, or tan colors. The Channeled Sea Star can reach up to 50 cm (20 inches) in diameter.

Habitat and Distribution:  Channeled Sea Stars are found on, or just under, the surface of mud and sand substrate. They reside from the intertidal zone to depths up to 180 m (585 feet). The Channeled Sea Star is a resident of Mexican waters of the Pacific and found in Bahia Vizcaino, Baja California southward along the west coast of the mainland to Guatemala. There is an isolated population in the Coronado Islands off the coast of the northern Baja. In the Sea of Cortez this sea star is found from the Midriff Islands, Baja California, to the greater Los Cabos area, Baja California Sur. There is also an isolated population know around Conzag Rock in coastal water off San Felipe in the extreme norther portion of the Sea of Cortez.

Synonyms:  Moiraster gigas, Sideriaster canaliculata and Tethyaster gigas.