Elephantfish (Callorhinchus milii)
Genome Project on Elephant Shark has launched to sequence the whole genome of the elephant shark. The elephant shark has three cone pigments for color vision (like humans). The elephant shark has a dorsal fin with a very sharp spine. The spine has been reputed to be venomous but no serious injuries have yet been reported. The genome of the elephant shark is estimated to be 910 Mb long (Mb = megabases = 1 million basepairs) which is the smallest among all the cartilaginous fishes and one-third the size of the human genome (3000 Mb).
Annual Migrations and Defence:
Males and females migrate from 200 m depths offshore to enter shallow coastal bays in spring and summer to breed. Here, females drop their golden-colored egg cases which hatch eight months later. Besides being well camouflaged, Elephant Fish defend themselves with a long serrated spine that is just in front of their first large dorsal fin. Elephant Fish often have green eyes, like the other chimaera species and deep-water sharks. When they are caught and hauled to the surface they have yet to react to the surface light and are still a startling metallic green. The body is silvery white, and sometimes has darker markings behind the eyes and on the fins.
Elephant Shark, Ghost Shark, Ghostshark, Plownose Chimaera, Reperepe, Silver Fish, White Fillets, Whitefish.
It grows to 1.2m in length.
The Elephantfish occurs off southern Australia and New Zealand.
It lives to depths of at least 200 and 500 meters deep on the continental shelf.
Other behaviors and adaptations:
The Elephantfish has a skeleton made of cartilage. Sharks and rays also have cartilaginous skeletons.
All three groups of fishes are classified in the class Chondrichthyes.
In spring, females migrate into coastal bays and estuaries to lay their egg cases in sand and muddy substrates. The distinctively-shaped egg cases are sometimes found washed ashore after storms. They are up to 25 cm long, 10 cm wide, and take up to eight months to hatch.
It is caught commercially in New Zealand and Southern Australia.