Fossil Ammonite Sigaloceras enodatum Jurassic Lower Callovian Kellaways UK

Description Authentic Jurassic Sigaloceras enodatum Ammonite from Ashton Keynes This listing offers a genuine Sigaloceras enodatum ammonite fossil from the Kellaways Formation, dating to the Lower Callovian Stage of the Jurassic Period (approximately 166–163 million years ago). The specimen was collected at Ashton Keynes in the United Kingdom, a locality renowned for its well-preserved ammonites and other marine fossils. As with all our items, this fossil comes with a Certificate of Authenticity guaranteeing it as a genuine specimen. The exact ammonite shown in the photographs is the one you will receive, with a 1 cm scale cube included to give a clear sense of size. This is a carefully chosen fossil, valued both for its scientific importance and natural beauty. Geological Context The Lower Callovian represents a key interval in the Jurassic when much of Europe, including Britain, was submerged beneath warm, shallow seas. These marine environments produced a rich fossil record, with the Kellaways Formation particularly noted for yielding exceptional ammonite specimens. The Kellaways deposits consist primarily of marine mudstones and siltstones, reflecting a relatively low-energy seabed environment. Such conditions allowed for the preservation of ammonites like Sigaloceras enodatum, along with bivalves, brachiopods, and occasional marine reptile remains. Ashton Keynes, where this fossil was found, is a well-documented fossil site within this formation. Scientific Classification Type: Fossil Ammonite Genus: Sigaloceras Species: enodatum Order: Ammonitida Superfamily: Stephanoceratoidea Family: Parkinsoniidae Age: Lower Callovian, Jurassic (~166–163 million years ago) Locality: Ashton Keynes, United Kingdom Formation: Kellaways Formation Morphological Features This Sigaloceras enodatum displays classic features associated with the species and family: Shell Form: Moderately involute coiling with compressed whorls, giving a streamlined appearance. Ribbing: Strong, well-defined ribs extend across the flanks, often bifurcating toward the outer edge of the shell. Ornamentation: Sigaloceras species are known for their intricate rib structures, which are highly diagnostic. Sutures: Complex suture lines can be observed, providing beautiful natural patterns and insights into the evolutionary complexity of ammonites. These features make Sigaloceras enodatum a highly recognisable and scientifically valuable ammonite from the Callovian stage. Paleoecology and Significance Ammonites like Sigaloceras enodatum were active predators in the Jurassic seas, preying on smaller mollusks, crustaceans, and plankton. Their streamlined shells and buoyant chambers allowed them to move efficiently through the water column. As a member of the family Parkinsoniidae, Sigaloceras represents a lineage of ammonites that were both ecologically important and geographically widespread. Their distinctive shells provide crucial data for geologists, as they serve as index fossils, enabling the dating and correlation of Jurassic rock sequences across Europe. The Kellaways Formation, where this fossil was found, is particularly significant because its ammonite assemblages help define Callovian biozones, making specimens like this one valuable for both scientific research and private collections. Collecting Value This specimen is not only a genuine piece of Jurassic history but also a rare example of Sigaloceras enodatum from the well-documented Kellaways Formation. Its strong ribbing, attractive coiling, and excellent preservation make it ideal for collectors who seek quality ammonites from British localities. Whether displayed as a natural art piece or studied as a paleontological specimen, this ammonite fossil offers both aesthetic appeal and scientific importance. Its provenance from Ashton Keynes, UK, enhances its desirability, as specimens from this locality are increasingly sought after. Key Features Species: Sigaloceras enodatum Age: Lower Callovian, Jurassic (~166–163 million years old) Formation: Kellaways Formation Locality: Ashton Keynes, United Kingdom Notable Traits: Well-defined ribbing, classic Callovian ammonite morphology Authenticity: Guaranteed genuine with Certificate of Authenticity Exact Item: The specimen photographed is the one you will receive This Jurassic ammonite fossil is a unique opportunity to own a scientifically important and beautifully preserved example of Sigaloceras enodatum from one of Britain’s most renowned fossil-bearing formations.