High Quality Content by WIKIPEDIA articles! The blotchy swell shark or Japanese swellshark (Cephaloscyllium umbratile) is a common species of catshark, family Scyliorhinidae, found at depths of 90–200 m (300–660 ft) in the northwestern Pacific Ocean from Japan to Taiwan. It is benthic in nature and favors rocky reefs. Reaching 1.4 m (4.6 ft) in length, this thick-bodied shark has a broad head, large mouth, and two unequally-sized dorsal fins positioned far back past the pelvic fins. It can be identified by its dorsal coloration, consisting of seven brown "saddles" and extensive darker mottling on a light tan background. This species has often been confounded with the draughtsboard shark (C. isabellum) and the Sarawak pygmy swellshark (C. sarawakensis) in scientific literature.