A shark said to be a “living fossil”.
On January 27, 2007, fishermen in Japan have found a very strange fish swimming near the surface of the sea. The animal was identified as the shark-snake (Chlamydoselachus anguineus), rare species that inhabits the deep ocean.
Considered a true living fossil by scientists – there are fossils of this species which date approximately 80 million years – the shark-snake has a few changes with respect to their ancestors.
There are few studies abouy the shark-snake, because he usually lives at depths that are beyond human reach. However, the rare information collected by scholars in the subject reveal some very interesting data about the Chlamydoselachus anguineus.
Champion of diving
Acording to the Japanese Tadashi Kubota, the shark-snake was found disoriented and sick, probably because of changes in sea currents. These changes may have been caused by the melting of glaciers due to global warming.
Typically, the shark-snake lives at depths greater than or equal to 600 meters. To get an idea of the difficulty of access to their habitat, remember that a diver descends unattended, no more than 40 meters deep.
Humans out of danger
The shape of the shark-snake body, is similar to an eel, but acording to its head, scientists consider in the family of sharks. Thanks to the presence of cracks branchial and ampoules of Lorenzini, the scientists were able to classify it as a shark. While most sharks have five pairs of gills, sharks-snake have six.
Like his brothers, the shark-snake is a predator, but presents no danger to humans, despite their size can reach two meters in length.
This fish has a long jaw and equipped with 300 pointed teeth , distributed in 25 rows. They are part of his menu the squid, and possibly smaller sharks.
Gestation period of the shark-snake
A recent study by Sho Tanaka, a biologist at the University of Tokai, Japan, shows that the period of gestation of the Chlamydoselachus anguineus lasts three and a half years, that is almost twice the period of gestation of a female African elephant ( 22 months).
In his work, Sho Tanaka examined 264 shark-snake’s. The animals did not demonstrate a reproductive season, which means they can couple in any season. This may have been an adjustment related to the long period of gestation, according to the scientist.
Another interesting revelation by Tanaka’s study is that the shark-snake produces the lowest number of pups among the species of his order. The shark-snake produces an average of six ”pups” every pregnancy.
The shark-snake is threatened with extinction due to human action. Its market value is low, but sometimes this animal is trapped in fishing nets and dies. His delay in producing offspring can not compete with the demand of the fishing industry. Moreover, global warming is another factor that contributes to their extinction.
The Chlamydoselachus anguineus faced 80 million years of changes in the planet Earth, but seems unable to resist the human action.