Small, long, brown shark found in deep water

The Brown catshark (Apristurus brunneus) is a shark belonging to the family Scyliorhinidae. It can be found in the east Pacific Ocean, ranging from the northern Pacific waters off the coast of southeast Alaska to Mexico. They may live as far south as Ecuador and Peru. Brown catsharks are deep-water sharks that live on the outer continental shelf and the upper slope. They have been known to live at depths ranging from 108-4,259 feet. The Brown catshark, when originally described, was called Catulus brunneus. They are small and dark brown in color with elongated bodies that are described as flabby and soft.


Family: Scyliorhinidae – Catsharks

Genus: Apristurus 

Species: brunneus


Phylum– Chordata

Class– Chondrichthyles


Common NameGround Sharks

Family– Scyliorhinidae

Common NameCatsharks




Average Size and Length: The egg cases measure 5×2.5 cm. Hatchlings measure between 7-9 cm. Mature males have been measured between 45-50 cm/1.5-1.6 feet. Mature females have been measured between 42-48 cm/1.4-1.6 feet. The maximum recorded has been 69 cm/2.3 feet.

Teeth and Jaw: The mouth is long and arched. The labial furrows are very long. The lowers are shorter than the uppers. The teeth are long and straight to a point, with the bottom teeth wider than the slenderer upper teeth.

Head: The head is broad and flattened with a long snout. The nostrils are large. The mouth extends about opposite front of the eyes.

Denticles: Their skin is weak and easily damaged.

Tail: The caudal fin is elongated.

Demographic, Distribution, Habitat, Environment and Range: The Brown catshark can be found in the east Pacific from southeast Alaska to north Mexico (60°N – 18°S, 167°E – 71°W). They may possibly be found in Panama, Ecuador and Peru. They can be found over the outer continental shelves and the upper slopes between 108-4,259 feet. They can be found on, and well above the bottom. Migratory patterns are not known or confirmed. They are demersal cold to subtropical.

Diet: They eat small bottom shrimp, squid and small fish.

Aesthetic Identification: The Brown catshark has a long and slender dark brown body. It has obvious light posterior margins on the fins and on the upper tail edge. The gill slits are less than the length of the adult eye length. The dorsal fins are of equal size. The first dorsal fin’s origin is over the pelvic fin midbases. There is a small notch between a very large elongated anal fin. Their bodies have been described as soft and flabby.

Biology and Reproduction: The Brown catshark is oviparous. They lay pairs of eggs (single egg at a time per oviduct) inside egg cases that have long tendrils. The egg case is transparent. They lay their eggs in the spring and in the summer in Canada. They may take a year to hatch. 

Behavioral Traits, Sensing and Intelligence: Unknown. Some suggest they are nocturnal and solitary, but this is not confirmed. Some suggest that they have a strong sense of smell and utilize their ampullae of Lorenzini.

Brown Catshark Future and Conservation: They are not evaluated. They have been caught as bycatch from deepwater fisheries.

Brown Catshark Recorded Attacks on Humans: Not a threat to humans.