sailfin roughshark

Rare deep-water shark with fins like sails

The Sailfin roughshark (Oxynotus paradoxus) is a species belonging to the order of Dogfish shark in the family Oxynotidae (Roughsharks), found in the eastern North Atlantic from Scotland to Senegal between latitudes 61°N and 11°N, at depths of between 869 and 2,461 feet. Its maximum recorded length is up to 3.9 feet.


Family: Oxynotidae – Roughsharks

Genus: Oxynotus 

Species: paradoxus


Phylum– Chordata

Class– Chondrichthyles



Common NameDogfish Sharks

Family– Oxynotidae

Common Name– Roughsharks




Average Size and Length: Mature males have been recorded at 2.5 feet. The maximum known length of the Sailfin roughshark is 3.9 feet. Newborn pups have been recorded at around 10 inches.

Teeth and Jaw: The top teeth of the Sailfin roughshark are lanceolate, but the lower teeth are blade-like. Each set of both upper and lower teeth contain 12 rows of teeth.

Head: The Sailfin roughshark has a blunt snout and a wide, flattened head. Both spiracles are relatively small compared to other sharks and are almost completely circular.

Denticles: The flank dermal denticles contain a central cusp next to two lateral cusps and a second middle cusp above the primary cusp.

Demographic, Distribution, Habitat, Environment and Range: The Sailfin roughshark is found in the eastern North Atlantic from Scotland to Senegal and the Mid-Atlantic Ridge between latitudes 61°N and 11°N, at depths of between 869 and 2,461 feet. In the Eastern Central Atlantic, it has also been reported to be found on the shores of Morocco, the Gulf of Guinea and in the Azores. They are bathybenthic.

Diet: The diet of the Sailfin roughshark is unknown, however research suggests that they are a predator of small, benthic animals.

Aesthetic Identification: The Sailfin roughshark is uniform dark brown when alive, however researchers have noted that preserved specimens turn black. It has a compressed body. It has two tall, narrow and pointed dorsal fins that contain concave trailing edges, but no anal fin. The first dorsal spine trails back, a unique feature. This is the only species in its family to have an inclined first dorsal spine.

Biology and Reproduction: Sailfin roughsharks are ovoviviparous.

Behavioral Traits, Sensing and Intelligence: Unknown.

Speed: The Sailfin roughshark is through to be a slow-moving shark.

Sailfin Roughshark Future and Conservation: The Sailfin roughshark is an uncommon bycatch of bottom trawls, but not enough data has been collected to properly evaluate this shark.

Sailfin Roughshark Recorded Attacks on Humans: Not a threat to humans.