The chain catshark (Scyliorhinus retifer) is a small species of catshark belonging to the family Scyliorhinidae. It occurs in the western Atlantic Ocean along the eastern coast of North America, from the Gulf of St. Lawrence to the Gulf of Mexico.

The species is easily recognised by the dark chain-like pattern covering its body, from which its common name is derived. Usually brown to grey in colour, the chain catshark uses this intricate patterning as camouflage against sandy, rocky, and soft-bottom habitats on the seafloor. It has an elongated body, two small dorsal fins set far back, and a slender tail.

The chain catshark is a relatively small shark, rarely exceeding 59 cm (23 in.) in length[1]. Primarily nocturnal, it feeds on small fishes, crustaceans, worms, and other bottom-dwelling organisms.

The chain catshark is oviparous, meaning it lays eggs rather than giving birth to live young. Females deposit protective egg cases — often called “mermaid’s purses” — in sheltered areas on the seafloor. These egg cases possess long tendrils at their corners that help anchor them to sponges, corals, sea pens, or other underwater structures.

Like many catshark species, the chain catshark has little commercial importance and is rarely targeted by fisheries, partly because it often inhabits rough or complex bottoms poorly suited to trawling. It is generally found at depths ranging from 58 to 550 m along the continental shelf and upper slope[2].

The chain catshark may be a relatively rare seasonal visitor, or possibly even a permanent resident of the Gulf of St. Lawrence, although available data remain insufficient to clearly determine its status in the region.

(1) Castro, J. 2011. The Sharks of North America. Oxford University Press, 613 p.
(2) Gilhen, J., B. W. Coad, and A. Hebda. 2003. The chain dogfish, Scyliorhinus retifer (Garman, 1881), new to the Canadian Atlantic ichthyofauna. Canadian Field-Naturalist 117 (3): 475-477.

• Chain-like markings: One of the most distinctive features of the chain catshark is the network of dark, interconnected markings covering its body, from which its common name is derived. These chain-like patterns extend along the sides, back, and fins, helping the shark blend into rocky and soft-bottom habitats.
• Size and shape: The chain catshark is a small, slender shark with an elongated body adapted to a benthic (bottom-dwelling) lifestyle. It rarely exceeds 59 cm (23 in.) in length[1].
• Colouration: The species is generally yellowish-brown to grey, a coloration that provides effective camouflage on the seafloor.

• Dorsal fins: It possesses two small, spineless dorsal fins positioned far back on the body, close to the tail.
• Teeth: The chain catshark has numerous small, sharp teeth adapted for grasping small prey such as fishes, crustaceans, and worms.
• Barbels: Unlike some bottom-dwelling sharks, the chain catshark lacks barbels near the nostrils.

(1) Castro, J. 2011. The Sharks of North America. Oxford University Press, 613 p.

The chain catshark (Scyliorhinus retifer) occurs primarily in the western Atlantic Ocean along the eastern coast of North America, from the Gulf of St. Lawrence to the Gulf of Mexico. It is generally associated with continental shelves and upper slopes, inhabiting sandy, rocky, and soft-bottom habitats at depths ranging from approximately 58 to 550 m[1]. The species is also commonly found near underwater structures that provide shelter and concealment.

Adapted to temperate and subtropical waters, the chain catshark is considered relatively common throughout much of its range. Its local distribution may nevertheless vary according to factors such as depth, temperature, and prey availability.

In Atlantic Canada, the species has been observed only rarely, including off Nova Scotia and in the Gulf of St. Lawrence.

(1) Gilhen, J., B. W. Coad, and A. Hebda. 2003. The chain dogfish, Scyliorhinus retifer (Garman, 1881), new to the Canadian Atlantic ichthyofauna. Canadian Field-Naturalist 117 (3): 475-477.

The chain catshark (Scyliorhinus retifer) has not been assessed by COSEWIC (Committee on the Status of Endangered Wildlife in Canada) and is not currently listed under Canada’s Species at Risk Act (SARA). In Canada, the species remains poorly documented and appears to be rare in Atlantic Canadian waters, including the Gulf of St. Lawrence.

Globally, the chain catshark is classified as Least Concern by the International Union for Conservation of Nature (IUCN). Although it is occasionally taken as bycatch, the species is not targeted commercially and is considered relatively common throughout much of its western Atlantic range. Its deepwater habits and limited commercial value currently reduce direct fishing pressure on the species.