roughskin dogfish

A shark wanted for its squalene

The Roughskin dogfish (Centroscymnus owstonii) is a Sleeper shark of the family Somniosidae, found around the world on continental shelves in tropical, subtropical and temperate seas, at depths of between 328 and 4,921 feet.


Family: Somniosidae – Sleeper sharks

Genus: Centroscymnus 

Species: owstonii


Phylum– Chordata

Class– Chondrichthyles



Common NameDogfish Sharks

Family– Somniosidae

Common NameSleeper Sharks




Average Size and Length: The Roughskin dogfish is born at 11.8 inches. Males reach a length of 2.4 feet, and females 3.3 feet. The maximum recorded length is 3.9 feet.

Teeth and Jaw: Similar to the Portuguese dogfish, but smaller cusps. The lips are thick and smooth, the mouth is slightly arched, and a bit narrower than the Portuguese dogfish. The upper teeth are slender and upright.

Head: Long snout, the head is similar to the Portuguese dogfish. It is flat and broadly rounded. The eyes are oval and large, and are equipped with tapetum lucidum. The nostrils have short skin flaps.

Denticles: Similar to the Portuguese dogfish, but smaller. They also resemble the scales of bony fishes.

Demographic, Distribution, Habitat, Environment and Range: The Roughskin dogfish can be found in the West Atlantic in the Gulf of Mexico, Brazil, Uruguay. In the East Atlantic, they are found in the Canary Islands and Madeira to South Africa. In the Pacific, they are found in Japan, Australia to the southeast.

They are found on or near the bottom of the continental shelves and submarine ridges 1397- 4787 feet. They are usually found greater than 1969 feet. Females seem to stay deeper than males in Japan.

Diet: They mainly eat bony fishes and cephalopods.

Aesthetic Identification: They are extremely similar in appearance to the Portuguese dogfish, but a longer lower first dorsal fin, and a slightly taller more triangular second dorsal fin. The dorsal fin spines are slightly exposed.

Biology and Reproduction: The Roughskin dogfish is ovoviviparous and they have up to 35 eggs per female, but the litter size is unknown.

Behavioral Traits, Sensing and Intelligence: The Roughskin dogfish is known to school. Sometimes they segregate by sex. Like the Portuguese dogfish, they have exceptional eyesight.

Roughskin Dogfish Shark Future and Conservation: It is of interest to local fisheries, caught bycatch. It is processed for fishmeal and squalene.

Roughskin Dogfish Shark Recorded Attacks on Humans: Not a threat to humans.