Featured Elasmobranch – Longnose catshark

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Featured Elasmobranch – Longnose catshark

March 2009





Identification: A small, moderately slender catshark with a long, broad snout, large gill slits, small eyes, lower labial furrows longer than upper, and a continuous supraorbital sensory canal. The first dorsal fin base is about equal in length to the second dorsal fin base with origin posterior to origin of pelvic fin. Second dorsal fin is broader and higher than first dorsal fin, originating posteriorly to origin of anal fin. Anal fin is short, very high and rounded with insertion anterior to second dorsal fin. Caudal fin is without crest of enlarged denticles on its upper margin. Color is a uniform blackish with prominent white posterior margins on precaudal fins.

Size: A maximum reported total length for males is 64.7 cm total length and for females it is 59.0 cm total length.

Distribution: Eastern North Pacific from Cape Blanco, Oregon, to central and southern California, USA and southward to the Gulf of California, Mexico.

Habitat: A deepwater, mainly bottom dwelling species found on the upper continental slope, ranging from 180 to 1888 m.

Biology: Oviparous, with a single egg case deposited per oviduct. Egg cases are typically thick-walled, measuring 6.1 to 7.1 cm in length, and lack tendrils. Embryos rely entirely on a yolk-sac during development. Newborns have two rows of enlarged denticles along their back that aid them in escaping from the egg case, which disappear shortly after birth. Size at birth is approximately 14 cm. Males usually mature at about 48 cm and females mature at about 49 cm total length. Diet consists of deepwater crustaceans (euphausiids and penaeid shrimps), cephalopods, and small bony fishes.

General interest: The longnose catshark is a poorly known species due to its deepwater habitat and confusion with other Apristurus species. Because this species is poorly studied, it is currently listed as data deficient (DD) by the IUCN. It is incidentally taken in deepwater trawls and sablefish traps off California. There have been reports of a similar or closely related species from off the Galapagos Islands, but this may in fact be an undescribed species.

By Jenny Kemper
Pacific Shark Research Center
Moss Landing Marine Laboratories
8272 Moss Landing Road, Moss Landing, CA 95039