Frill shark

Frilled shark Temporal range: – Holocene PreЄ Є O S D C P T J K Pg N ↓
Conservation status
Least Concern (IUCN 3.1)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Chondrichthyes
Order:	Hexanchiformes
Family:	Chlamydoselachidae
Genus:	Chlamydoselachus
Species:	C. anguineus
Binomial name
Chlamydoselachus anguineus Garman, 1884
Range of the frilled shark

The frilled shark (Chlamydoselachus anguineus) is one of two extant species of shark in the family Chlamydoselachidae, with a wide but patchy distribution in the Atlantic and Pacific Oceans. This species is found over the outer continental shelf and upper continental slope, generally near the bottom, though there is evidence of substantial upward movements. It has been caught as deep as 1,570 m (5,150 ft), although it is uncommon below 1,200 m (3,900 ft). In Suruga Bay, Japan, it is most common at depths of 50–200 m (160–660 ft). Exhibiting several "primitive" features, the frilled shark has often been termed a "living fossil". It reaches a length of 2 m (6.6 ft) and has a dark brown, eel-like body with the dorsal, pelvic, and anal fins placed far back. Its common name comes from the frilly or fringed appearance of its six pairs of gill slits, with the first pair meeting across the throat.

Seldom observed, the frilled shark may capture prey by bending its body and lunging forward like a snake. The long, extremely flexible jaws enable it to swallow prey whole, while its many rows of small, needle-like teeth make it difficult for the prey to escape. It feeds mainly on cephalopods, leavened by bony fishes and other sharks. This species is aplacental viviparous: the embryos emerge from their egg capsules inside the mother's uterus, where they survive primarily on yolk. The gestation period may be as long as three and a half years, the longest of any vertebrate. Litter sizes vary from two to fifteen, and there is no distinct breeding season. Frilled sharks are occasional bycatch in commercial fisheries, but have little economic value.