The Frill or Frilled Shark (Chlamydoselachus anguineus), a primitive shark species, resembles a dark brown or grey eel, but the six gill slits identify it as a shark. The tissue of the gill slits protrudes somewhat, thus inspiring the common name. Its dorsal fin is small, anal fin large, and the caudal fin (tail fin) is highly asymmetric, the dorsal part almost unnoticeable. Its teeth are small, tricuspid, and very sharp. It has been recorded at up to 6.5 feet (2 m) in length.
Distribution is worldwide, but they are very rarely found in shallow water. They have been reported in all oceans but are mainly found near Norway, South Africa, New Zealand, and Chile. The sharks are usually found at depths of between 165 feet and 5000 feet(50 m and 1,500 m).
There is no information on population size anywhere.
Here is a picture taken of a Frilled Shark accidently caught off the waters in Japan and taken to a marine park. The specimen was apparently sick because it died only a few hours after it was caught.