Ammonite - Fossilised animal - Aioloceras (Cleoniceras) sp. - 150 mm - 130 mm





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Aioloceras (Cleoniceras) sp., Ammonite specimen from Madagascar, Late Cretaceous period (100.5–66 million years ago), treated and polished, condition: worked.
Description from the seller
A very important fossil group from the Devonian-Cretaceous period. Completely extinct by the end of the Cretaceous, it is believed to have descended from ancestors belonging to Nautiloidea. Although part of the mollusk cephalopod group, CLEONICERAS is distinguished mainly by the shape of its shell, characterized by bilateral symmetry. The shell is divided into an anterior, undivided region where the animal resided, and a posterior region divided into chambers. The line of closure between the chambers is highly indicative and facilitates species recognition. Additionally, its outline, initially quite simple and linear in early forms, gradually changed until the more recent ammonites, which are often very jagged and almost baroque. Sizes vary: from a few centimeters to as much as 10 centimeters. Since these are entirely extinct marine species, we can only hypothesize about their lifestyle. It is believed that forms with smooth shells on the outside were swimmers, often predators. Species with more costate and ornamented shells were predominantly benthic.
Unmissable Lotto
Impressive and splendid specimen of Cleoniceras, sectioned to reveal its extraordinary internal structure, made possible by the fossilization process through silicification. This natural process gradually replaces the original organic tissues with silica, a mineral that fills the shell's cavities and transforms them into a sparkling composition of quartz and calcite crystals, exceptionally preserving the internal details and turning the fossil into a true work of nature's art.
Particularly visible is the dark color typical of black hematite, which gives this ammonite a unique charm.
Observing the outer part of this beautiful fossil, the characteristic suture lines of the species are clearly visible, intertwining in a pattern that resembles the sinuous movements of flames.
A true natural masterpiece.
Pedestal not included, made from recycled materials used solely for photographic purposes.
Seller's Story
A very important fossil group from the Devonian-Cretaceous period. Completely extinct by the end of the Cretaceous, it is believed to have descended from ancestors belonging to Nautiloidea. Although part of the mollusk cephalopod group, CLEONICERAS is distinguished mainly by the shape of its shell, characterized by bilateral symmetry. The shell is divided into an anterior, undivided region where the animal resided, and a posterior region divided into chambers. The line of closure between the chambers is highly indicative and facilitates species recognition. Additionally, its outline, initially quite simple and linear in early forms, gradually changed until the more recent ammonites, which are often very jagged and almost baroque. Sizes vary: from a few centimeters to as much as 10 centimeters. Since these are entirely extinct marine species, we can only hypothesize about their lifestyle. It is believed that forms with smooth shells on the outside were swimmers, often predators. Species with more costate and ornamented shells were predominantly benthic.
Unmissable Lotto
Impressive and splendid specimen of Cleoniceras, sectioned to reveal its extraordinary internal structure, made possible by the fossilization process through silicification. This natural process gradually replaces the original organic tissues with silica, a mineral that fills the shell's cavities and transforms them into a sparkling composition of quartz and calcite crystals, exceptionally preserving the internal details and turning the fossil into a true work of nature's art.
Particularly visible is the dark color typical of black hematite, which gives this ammonite a unique charm.
Observing the outer part of this beautiful fossil, the characteristic suture lines of the species are clearly visible, intertwining in a pattern that resembles the sinuous movements of flames.
A true natural masterpiece.
Pedestal not included, made from recycled materials used solely for photographic purposes.

