roughskin spurdog

True to its name, a shark with rough skin to the touch

The Roughskin Spurdog (Cirrhigaleus asper) is a shark that belongs to the family of Dogfish or Squalidae, found circumglobally between latitudes 35°N and 35°S, at depths of between 656-1,970 feet. It reaches a length of 3.9 feet.


Family: Squalidae – Dogfish Sharks

Genus: Cirrhigaleus 

Species: asper


Phylum– Chordata

Class– Chondrichthyles



Common NameDogfish Sharks

Family– Squalidae

Common Name– Dogfish Sharks




Average Size and Length: The maximum reported length of the Roughskin Spurdog is 3.9 feet. The average size is about 3 feet. Males reach maturity at length of 2.8-3.0 feet and females mature at 2.9-3.9 feet in length.

Current Rare Mythical Sightings: English common names include Roughskin Dogfish, Roughskin Dogshark and Roughskin Spiny Dogfish.

Teeth and Jaw: The Roughskin Spurdog has oblique teeth with smooth-edged cusps and distinct notches in the outer margins. The teeth are numbering 12-14 teeth on each side of the upper jaw and 11-12 teeth on each side of the lower jaw. This forms almost a continuous cutting edge. 

Head: The snout of the Roughskin Spurdog is broadly rounded and flat with anterior nasal flaps with short stubby barbels. The eyes and spiracles are large.

Denticles: The Roughskin Spurdog has skin that feels rough to the touch. This is where the common name originates. This rough texture is from the unusually large dermal denticles. The denticles on adult specimens are tripcuspidate with a distinct central ridge flanked by weaker ridges. Juveniles have leaf-shaped denticles characterized by a distinct central ridge.

Tail: The caudal fin is short with broad lobes and the subterminal notch on caudal fin absent.

Demographic, Distribution, Habitat, Environment and Range: The Roughskin Spurdog has been reported from the western Atlantic Ocean from waters off North Carolina to the Florida Keys as well as the northern Gulf of Mexico. In the western Indian Ocean, it is found from southern Mozambique to South Africa and waters off Reunion, Comoros, and the Aldabra islands. In the central Pacific Ocean, it lives off the shores of the Hawaiian Islands.

It can be found in marine waters over the upper continental and insular slopes. It is a deepwater species, found at depths from 656-1,970 feet. However, it has been reported as shallow as 240 feet. It is sometimes also found in bays and river mouths.

Diet: They feed on a variety of bony fishes and cephalopods including squid.

Larger sharks are potential predators.

Aesthetic Identification: The Roughskin Spurdog has a stout body. The body of the Roughskin Spurdog is dark gray to brown, fading to a counter-shaded lighter color below. The fins are edged with white. The body lacks spots or any other distinctive markings. Juvenile Roughskin Spurdogs are brown. The two dorsal fins each have a very large spine. The first dorsal fin originates behind the free rear tips of the pectoral fins. The second dorsal fin is large, approaching the size of the first dorsal. The triangular pectoral fins are broad and have rounded tips. There is no anal fin.

Biology and Reproduction: The Roughskin Spurdog is ovoviviparous with 18 to 22 pups per litter. Pups measure about 9.8-11 inches at birth.

Behavioral Traits, Sensing and Intelligence: Unknown.

Roughskin Spurdog Future and Conservation: There is no interest in commercial fisheries. It is occasionally caught with hook and line as well as trawling gear used in deep water. There is not enough data to accurately assess this shark.

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