Latimeria

Description

Anatomy

The coelacanth is a Poisson Crossoptérygien. It is thus a osseous fish whose average weight is of 80 kg for 1,50 meters length, certain specimens being able to reach the 2 meters length.

Its blue or brown thorny scales are finer than those of other fish.

It resembles very extremely its ancestors which one found many fossils. The males are smaller than the females.

The study of Latimeria allowed, inter alia, to know the role of the body rostral, whose presence at the fossils remained until there a enigma. To nourish itself, the Latimeria stroke the head towards the floor récifal, and thanks to the body rostral, it detects the weak electric field caused by a possible prey dissimulated under a fragment of reef. It nourishes invertebrates, small fish, and perhaps of corals.

Its manner of being driven would point out that of the Tétrapode S.

Lifestyle

The first specimens of Latimera were discovered in 1952 with average depths (between 100 and 400 meters) in the north of the channel of Mozambique close to the archipelago of the the Comoros.

They often take refuge in the underwater caves, which makes them difficult to observe and explains partly why the specialists a long time believed this disappeared species. One listed some less than 200 specimens, all in the Indian Ocean.

Reproduction

One discovered in 1975 that Latirneria were, like the Holophagus penicillata of the Jurassic , Ovovivipare S. a polemic concerning the validity of this discovery made rage in 2000, of the articles published in the review Nature disputing the first information published on this discovery. But the genetic analyzes on these animals confirmed well that they acted of a species-sister: Latimeria menadoensis .

In June 2006, according to the daily newspaper indonésien Kompas, the oceanographical research Center indonésien and the Japanese museum Aquamarine Fukushima succeeded in taking photographs of five of these fish to a 150 meters depth, thanks to underwater cameras.

May 19th, 2007, Yustinus Lahama, a fisherman indonésien, and his son, took in their nets a coelacanth which measured 1,31 m and weighed 51 kg, off the coasts of the province of Sulawesi of North. They kept it on their premises during an hour, specified professor Grevo Gerung of the university of Sam Ratulangi. The fish was then placed in a park in seaside where he survived approximately 17 hours. " Withdrawn of its natural habitat, with an about sixty meters of depth, the coelacanths cannot normally live more than two hours. We will seek to know why this one held if longtemps" , Gerung said.

Today, the two species are registered on the lists of the Convention on the international business of the species of fauna and flora savages threatened of extinction (or QUOTE).

See too

There exist fish having true lungs: the Dipnoi.

External references

External bonds

Laurence Beltan, Which is the origin and in which place the parturition of the current coelacanth occurs: Latimeria chalumnae Smith, 1940 (Pisces Sarcopterygii)? , ORSTOM, 1996 (To read on line)

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