Chlamydoselachus Lo Squalo Preistorico

di hunterwhales

New exceptional discovery for the paleontological group GAMPS of Scandicci.
An ocean deep in the Siena countryside.
di Luca Oddone

This time it is a discovery destined to make a sensation in the scientific world and to amend the paleo ambient reconstructions of the ancient sea who once was the Sienese countryside. In Castelnuovo Berardenga, locality situated a few kilometres from Siena, have come to light in the famous Crete Senesi, an impressive number of fossil teeth of Chlamydoselachus anguineus, a species of shark with sinuous body, more similar to an eel, and from here the name, that not to a fish.

Animal, a true living fossil, still wanders around today on the ocean deeps, between 400 and 1600 metres below the surface of the ocean, moving with sudden changes of direction to the search of prey in the waters dark impenetrable to sun rays. The species fossil could reach more than two metres in length and seem considerably bigger of current populations that it could be considered as a species itself.
The discovery of these teeth, and the information from the sediments, have substantially amended the idea that we had about that part of the Mediterranean Pliocene that was the Tuscany.
Thin today, in fact, it was thought that in the Pliocene Medio (around three million years ago) the senese sea basin was not particularly deep, conviction that the presence of abyssal forms of life as the Chamydoselachus and the Centrophorus granulosus has disproven, so much to be replaced the traditional scenery with one new more variegated and complex, in which coastal zones or of low sea were alternated to true abysses that took form to little distance from the shore, there where a brief base of coast left the place to the steep continental scarp.
The hundred teeth of Chlamydoselachus discovered by Simone Casati in the last three years, so rare and precious, have been object of an important search now published on the international magazine:
CAINOZOIC RESEARCH A small fossil fish fauna, rich in Chlamydoselachus teeth, from the Late Pliocene of Tuscany (Siena, central Italy) Franco Cigala Fulgosi, Simone Casati, Alex Orlandini & Davide Persico
One of the authors of such job, professor Cigala Fulgosi, teacher at the Department of Earth Sciences in Parma, considered one of the maximum experts of sharks fossils in the world, have observed also the fact that this extraordinarily elevated number of teeth, some hundred, have relatively been found in a narrow area.
This makes to think that an unusual concentration of this species is due to the presence of tides sea particularly rich in nourishment or to the presence in the area of favourable conditions about the reproduction of these sharks. The scientific value of the discovery is in the fact that we have succeeded in determining exactly an oceanic pit to the border of a continental scarp, a sort of submarine canyon not very distant from the coast where were assembled hundreds of sharks that currently they are found only out of the Mediterranean Sea and, above all, to abyssal depth.
Thanks to the picked finds in over three years of searches, we have a photo of a moment of transition among the great opening post-messiniana happened in the inferior Pliocene and the geographical and ecological conditions of the actual Mediterranean Sea.

A thick concentration of these archaic sharks, offers a great possibility to understand what and how many changes the Mediterranean Sea has had in the last 5 million of years.
We can add that it is the first time that we have a direct relationship among the teeth of the snake shark and the information drawn by the sediment in which are deposited 3,5 million years ago.
Once more I feel me to say that the job of the group GAMPS of Scandicci has put a great scientific opportunity into practice, not only bringing again the naturalistic historical patrimony of Tuscany out, but in a certain way a patrimony of the whole Italian palaeontology in the international context.

Le foto pubblicate nel video di sono di Giam Paolo Faienza , Alex Orlandini e Simone Casati

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