Dissimilites dissimilis Heteromorph Ammonite Fossil France with COA

Description

This listing is for the exact genuine fossil shown in the photographs: a Dissimilites dissimilis heteromorph ammonite from Saint-Martin-d’Escarène in the Alpes-Maritimes region of France. It dates from the Lower Barremian stage of the Early Cretaceous Period and is supplied with our lifetime Certificate of Authenticity. The certificate records its identification, geological age and locality, providing a permanent reference for your collection.

Dissimilites is a striking heteromorph ammonite, belonging to a remarkable group whose shells developed forms very different from the familiar flat, tightly coiled ammonites. Heteromorph shells could pass through open curves, shafts and hook-like sections during growth. Dissimilites dissimilis is particularly collectable for this unusual morphology, which illustrates the evolutionary experimentation taking place among Early Cretaceous cephalopods. Its form makes the fossil an excellent comparison specimen alongside conventionally coiled ammonites.

The fossil comes from Saint-Martin-d’Escarène in the Alpes-Maritimes of southeastern France. During the Early Cretaceous, this region lay within a marine setting connected to the ancient Tethys Ocean. Sediments accumulated on and around the seabed, burying shells and other remains that would later become part of the complex geology of the Alpine region. Fossils from this area record warm marine ecosystems that supported ammonites and many other invertebrates. A specimen with a precise locality carries valuable geological context and a strong sense of place.

The Lower Barremian represents the earlier portion of the Barremian Stage, approximately 129 to 127 million years ago. Ammonites were cephalopod molluscs related to living squid, cuttlefish and nautiluses. Their chambered shells assisted with buoyancy while the living animal occupied the final body chamber. The unusual shell geometry of heteromorph ammonites may have affected orientation, swimming and feeding behaviour, and their palaeobiology remains an intriguing subject of research.

Ammonite lineages evolved quickly and many species were distributed across broad marine regions. Palaeontologists therefore use them as index fossils to correlate and date sedimentary rock sequences. A fossil with an identified species, stage and locality provides more than decorative appeal: it is a physical record of biological evolution, ancient marine life and the geological history of the Tethyan realm.

Please inspect every photograph carefully, as the images form an essential part of the description. You will receive the exact fossil pictured, not a stock example or a similar substitute. Natural matrix, surface texture, colour variation, incomplete shell areas, mineral deposits and small imperfections are normal features of an authentic fossil and are shown honestly. For full sizing and proportions, please use the measuring reference visible in the photographs.

This Dissimilites dissimilis would suit a collector of heteromorph ammonites, European fossils, Barremian cephalopods or Early Cretaceous life. Its unusual shape also makes it an effective educational specimen for explaining ammonite growth, adaptation and diversity. It would make a thoughtful gift for a fossil collector, geology student or natural history enthusiast.

The specimen will be packed carefully for dispatch. Handle it gently and display it in a stable, dry environment. The included generic lifetime Certificate of Authenticity identifies it as Dissimilites dissimilis, records its Lower Barremian age, and gives Saint-Martin-d’Escarène, Alpes-Maritimes, France as the locality. This is a genuine natural fossil with scientific, historical and display interest.