A newly described and rare shark

Stevens swellshark (Cephaloscyllium stevensi) is a species of catshark belonging to the family Scyliorhinidae, which can be found in the waters around western Papua New Guinea. It was described by Clark and Randall in 2011.


Family: Scyliorhinidae – Catsharks

Genus: Cephaloscyllium 

Species: stevensi


Phylum– Chordata

Class– Chondrichthyles


Common NameGround Sharks

Family– Scyliorhinidae

Common NameCatsharks




Average Size and Length: Females have been recorded at 66 cm/2.2 feet.

Demographic, Distribution, Habitat, Environment and Range: Steven’s swellshark can be found in western Papua New Guinea at a depth range of between 787-899 feet. They are considered tropical pelagic-neritic.

Ram-Suction Index: More than likely they are high on the suction side of the index.

Aesthetic Identification: Steven’s swellshark is similar to its congeners. It is most easily distinguished by its color pattern, being gray-brown above, and whitish ventrally, mottled with brown and whitish spots of variable size over the head and body, including ventrally. There are 6 large dark brown saddle blotches dorsally on the head and body, and 3 on the caudal fin. The first four dorsal dark blotches are connecting or leading obliquely to the other dark blotches below. The small white spots are most distinct within or at the edges of the dark brown blotches.

Biology and Reproduction: More than likely they are oviparous.

Behavioral Traits, Sensing and Intelligence: Like other members of its genus, Steven’s Swellshark can inflate its stomach with water (or air on land) in an effort to deter predators.

Speed: More than likely they are sluggish and slow.

Steven’s Swellshark Future and Conservation: They are not evaluated.

Steven’s Swellshark Recorded Attacks on Humans: Not a threat to humans.