Nautiloidea - Fossilised animal - cleoniceras in sezione - 13.6 cm - 11 cm

Very important group from a fossil point of view belonging to the Devonian-Cretaceous period. Totally extinct by the end of the Cretaceous, it is thought to have derived from ancestors belonging to the Nautiloidea. Although part of the group of cephalopod mollusks, CLEONICERAS is distinguished above all by the shape of the shell characterized by bilateral symmetry. The shell is divided into a front undivided region where the animal lived and a rear region divided into chambers. The line of closure between the chambers is very indicative and facilitates the recognition of the species. Moreover its outline, in the early forms rather simple and linear, has gradually changed up to the more recent ammonites where it is often very jagged and almost baroque. Sizes vary: it starts from a few cm but can reach up to 10 cm. Since these are entirely extinct marine species, one can only hypothesize their lifestyle. It is believed that forms with smooth shells externally were swimming, often predators. Species with more ribbed and ornamented shells were predominantly benthic. Unmissable lot: Excellent specimen of Cleoniceras sectioned to reveal the extraordinary internal structure, made possible by the fossilization process through calcite. Observation of the external part of this beautiful fossil clearly shows the characteristic sutural lines of the species, which intertwine in a pattern that recalls the sinuous movements of flames. A true natural masterpiece. Pedestal not included, obtained from salvaged materials used and used solely for photographic purposes.

Schätzpreis:€180

Alle Objekte ansehen vonCatawikioderEtnografica