A mysterious benthic shark

The Sarawak Pygmy swellshark (Cephaloscyllium sarawakensis) is a species of catshark, belonging to the family Scyliorhinidae. It is found in the benthic zone in the south China Sea. All known species have been collected by trawl nets.


Family: Scyliorhinidae – Catsharks

Genus: Cephaloscyllium 

Species: sarawakensis


Phylum– Chordata

Class– Chondrichthyles


Common NameGround Sharks

Family– Scyliorhinidae

Common NameCatsharks




Average Size and Length: They reach a maximum known length pf 40.8 cm/1.3 feet. Males mature at 32.5 cm/1.1 feet and females between 35.4-40.8 cm/1.2-1.3 feet.

Head: The anterior nasal flaps are triangular without an elongated flap.

Demographic, Distribution, Habitat, Environment and Range: The Sarawak Pygmy swellshark is found in the Pacific Ocean in the south China Sea in possibly western south Taiwan, Hong Kong, Gulf of Tongking, Vietnam, Malaysia. They are considered subtropical, benthopelagic, and so can be found in the benthic zone near the edge of the Pacific continental shelf, at depths of 387-541 feet.

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

Aesthetic Identification: Adult Sarawak Pygmy swellsharks have 2 distinct, wide brown saddle blotches before the first dorsal fin, while juveniles have 3. The first saddle is immediately behind the eye, and the second is over the posterior 1/3 of the base and inner margin of the pectoral fins. The third is a little before the first dorsal fin, which fades with growth. There are dark lateral circular to oblong blotches above the gill openings, and on the lateral side of the trunk. The young individuals have many polka dots on the body and fins.

Biology and Reproduction: More than likely they are oviparous.

Behavioral Traits, Sensing and Intelligence: Like other members of its genus, it has the ability to inflate its abdomen with water (or air n land) in an effort to deter predators.

Speed: They are more than likely sluggish and slow.

Sarawak Pygmy Swellshark Future and Conservation: There is not enough data to evaluate.

Sarawak Pygmy Swellshark Recorded Attacks on Humans: Not a threat to humans.