RARE Fossil Heteromorph Ammonite Acrioceras tabarelli – Upper Barremian, Cretaceous – France – Alice Purnell Collection

Description RARE FOSSIL HETEROMORPH AMMONITE – ACRIOCERAS TABARELLI Geological Age: Upper Barremian Stage, Early Cretaceous (~125 million years ago) Location: Hautes-Provence Alps, Southeastern France From the Alice Purnell Collection Comes with Certificate of Authenticity This is an exceptionally rare fossil specimen of the heteromorph ammonite Acrioceras tabarelli, collected from the renowned Upper Barremian marine strata in the Hautes-Provence Alps of France. Acrioceras is a genus of heteromorphic ammonites, known for its loosely coiled to helical, irregularly curved shell and complex ornamentation. These uncoiled forms are evolutionarily significant, representing adaptations in ammonite buoyancy and ecology during the Cretaceous. This particular fossil has been carefully selected for its preservation, displaying well-defined ribbing and characteristic uncoiled shell curvature. It is mounted in its original matrix with a 1cm scale cube shown in the photo for accurate sizing. The image displays the exact fossil you will receive, with provenance from the esteemed Alice Purnell Collection. GEOLOGICAL & TAXONOMIC INFORMATION: Species: Acrioceras tabarelli Age: Upper Barremian, Early Cretaceous Location: Hautes-Provence Alps, France Formation / Depositional Environment: Marine carbonate and marl sequences deposited in a warm, shallow epicontinental sea of the northern Tethyan margin Order: Ammonitida Superfamily: Ancyloceratoidea Family: Ancyloceratidae Shell Morphology: Loosely uncoiled with early helical to irregularly curved whorls Ornamented with pronounced ribs and occasional tuberculation Shell morphology suggests planktonic to nektobenthic lifestyle Biozone: Acrioceras tabarelli is found in the Aptian transition zones of the Barremian stage, associated with Gerhardtia sartousiana and Heteroceras faunal assemblages Identified by: Originally described and classified by Astier in the 19th century, revised in later taxonomic frameworks for Barremian heteromorphs DISPLAY & EDUCATIONAL VALUE: Fossils of Acrioceras tabarelli are highly sought-after by collectors and academic institutions for their unique form and biostratigraphic importance. This genus is a textbook example of heteromorph evolution and is useful in Cretaceous biostratigraphy of southern Europe. The rarity of complete or near-complete specimens from this region adds considerable value. INCLUDED WITH PURCHASE: The exact fossil shown in the listing photos Certificate of Authenticity 1cm scale reference for size verification Secure, professional packaging From the Alice Purnell Collection SUMMARY: An outstanding and rare heteromorph ammonite fossil from the Upper Barremian of France. This Acrioceras tabarelli is a scientifically and visually captivating specimen, perfect for collectors of Cretaceous marine fossils, ammonite evolution, and European geological history.