A small and rare shark

The Dwarf Oriental swellshark (Cephaloscyllium sp. Not yet described) is a rare catshark belonging to the family Scyliorhinidae. They are quite similar to the Japanese swellshark but have many differences from the shape of the snout to the color pattern. They are a dwarf species, and much like the other members of their genus, they have an inflatable stomach.


Family: Scyliorhinidae – Catsharks

Genus: Cephaloscyllium 

Species: sp. Not yet described


Phylum– Chordata

Class– Chondrichthyles


Common NameGround Sharks

Family– Scyliorhinidae

Common NameCatsharks


Species– sp. Not yet described


Average Size and Length: Hatchlings are unknown. Adolescent sharks have been measured at 42 cm/1.4 feet. Mature males have been measured between 36-39 cm/1.2-1.3 feet. Adult females have been measured between 42-44 cm/1.4-1.5 feet. The maximum recorded is greater than 44 cm/1.5 feet. More specimens need to be measured to have a better understand of their sizes.

Teeth and Jaw: The mouth is large. The mouth forms a broad arch, and lacks furrows at the corners. The small teeth have a central cusp flanked by a smaller cusplet on both sides.

Head: The Dwarf Oriental swellshark has a longer snout and longer anterior nasal flaps than the Japanese swellshark. There are ridges over the eyes. The small, horizontally oval eyes are placed high on the head and equipped with rudimentary nictitating membranes. A tiny spiracle lies closely behind each eye.

Tail: The caudal fin is large and broad, with the upper lobe longer than the lower and bearing a prominent ventral notch near the tip. It is slightly more arched than the Japanese swellshark.

Demographic, Distribution, Habitat, Environment and Range: The Dwarf Oriental swellshark can be found in the western Pacific Ocean in Vietnam, China, Taiwan and Japan. Their habitat is poorly known, they possibly live inshore.

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

Aesthetic Identification: The Dwarf Oriental swellshark is similar to the Japanese Swellshark or Blotchy Swellshark (Cephaloscyllium umbratile), but there are noticeable differences. The Dwarf Oriental swellshark has a simpler blotched color pattern with few dark spots and a small size. Like other members of its genus, the Dwarf Oriental swellshark has an inflatable stomach.

Biology and Reproduction: They are oviparous, but not much else is known.

Behavioral Traits, Sensing and Intelligence: The Dwarf Oriental swellshark has the ability to inflate its stomach with water (or air on land) in an effort to ward of potential predators or threats.

Speed: More than likely they are sluggish.

Dwarf Oriental Swellshark Future and Conservation: Not enough data to evaluate.

Dwarf Oriental Swellshark Recorded Attacks on Humans: Not a threat to humans.