Latimeria: sightings, finds, mysteries



by LORENZO CIOTTI

Latimeria: sightings, finds, mysteries

Although today only two species of latimeria or coelacanths are known, in the Paleozoic and Mesozoic the group of coelacantides was very numerous and included different genera and species; of these there are many fossils datable from the Devonian to the Cretaceous, a period after which the coelacanths apparently were considered extinct, following the mass extinction of the late Cretaceous period since up to now no fossils dating back to later times have been found.

The latimeria does not live only in deep waters, a fact proven by the low depth of draft of the nets of the fishermen who find it, by the now well-known encounters of divers with living specimens and by statistical observation, that the biologist P.L.

Florey reports in her treatise on this fish, that most of the catches occurred between a depth of 100 and 400 meters, while the greatest number of visual sightings during diving occurred between 190 and 210 meters, moreover her observations seem to indicate that the bathymetric oscillations of the 18 ° C isotherm can influence the depth of life of the animal.

On October 28, 2000, in the protected waters of the St. Lucia area, on the border with Mozambique, three divers Pieter Venter, Peter Timm, and Etienne le Roux, found a coelacanth at a depth of 104 meters. After having renamed themselves SA Coelacanth Expedition 2000, the three returned to the charge, this time armed with photographic equipment and with a group of other divers ready to follow them.

On November 27, four of them found three coelacanths, one of which was between 1.5 and 1.8 meters long, while the others measured about 1 / 1.2 meters. The divers managed to photograph and film the animals, but, once they surfaced, one of them died of a cerebral gas embolism as a result of an effort made to help a companion, Christo Serfontein, who had momentarily lost consciousness.

Between March and April 2002, the submarine Jago and the group of divers Fricke Dive Team managed to find, in the same area, a group of fifteen coelacanths, including a pregnant female, also managing to collect tissue samples of the animals.

. In 1997, Arnaz and Mark Erdmann were enjoying their honeymoon in Indonesia when, at the Manado Tua market on Sulawesi, they noticed what looked like a gombessa on the stalls, but was brown instead of blue. After an expert noticed the photo of the fish they published on the internet, DNA tests were carried out, which showed that the species, called by the Indonesians king of the sea, was not the same as the coelacanth of the Comoros; the new species was called Latimeria menadoensis.

The first evidence of the existence of living coelacanths came in 1938 when Marjorie Courtenay-Latimer, curator of a museum in East London, South Africa, in examining the haul of local fishermen for unusual marine fauna, came across a strange fish.

blue among the catch of a fishing boat who went hunting for sharks in the Indian Ocean at the mouth of the Chalumna River.