Cardioceras questicardia Fossil Ammonite Lower Oxfordian Jurassic Ammonite Dorset UK

Description

Authentic Cardioceras questicardia Ammonite Fossil

Presented here is a genuine Cardioceras questicardia ammonite fossil from the Lower Oxfordian Stage of the Jurassic Period, discovered in Dorset, United Kingdom. This fossil dates to approximately 163–160 million years ago, during a time when much of southern England lay beneath warm, shallow seas teeming with marine life. The specimen has been carefully selected for its scientific and aesthetic qualities, making it a superb addition to any fossil collection. The photographs provided show the exact fossil you will receive, and a Certificate of Authenticity is included with your purchase.

Geological Background

The Oxfordian Stage is the opening stage of the Upper Jurassic, a period marked by the flourishing of ammonites, belemnites, bivalves, and marine reptiles. The Lower Oxfordian deposits of Dorset, particularly the Oxford Clay Formation and related sediments, are internationally renowned for their fossil richness and outstanding preservation.

Cardioceras questicardia is one of the characteristic ammonite species from this interval, and its occurrence is tied to stratigraphic zones used by palaeontologists to define precise layers of geological time. Dorset’s ammonite fossils not only reflect the diversity of ancient seas but also serve as essential tools for correlating rock layers across Europe.

Scientific Classification

• Species: Cardioceras questicardia
• Genus: Cardioceras
• Family: Cardioceratidae
• Superfamily: Stephanoceratoidea
• Order: Ammonitida
• Class: Cephalopoda
• Age: Lower Oxfordian, Jurassic (~163–160 million years ago)
• Locality: Dorset, United Kingdom

Morphological Features

This ammonite species is noted for its evolute coiling and sharply defined ribbing, features that are particularly striking in well-preserved specimens. The ribs radiate strongly from the umbilicus, curving gracefully across the whorls and often bifurcating towards the outer shell. These ornamented shells reflect the evolutionary adaptations of ammonites, possibly serving structural or hydrodynamic functions.

The suture lines, where internal shell walls met the outer shell, are complex and highly intricate—another hallmark of Jurassic ammonites. The bold ribbing pattern of Cardioceras questicardia makes it one of the more visually impressive species within its genus, easily distinguishable to both collectors and palaeontologists.

Stratigraphic and Scientific Importance

Members of the genus Cardioceras are considered key index fossils of the Oxfordian Stage, enabling geologists to divide and correlate Jurassic strata with great accuracy. Cardioceras questicardia is part of this important group and plays a role in refining ammonite biozonation. Its presence in Dorset deposits provides evidence of the evolutionary and ecological changes that took place in marine faunas as the Jurassic progressed into its later stages.

Depositional Environment

During the Lower Oxfordian, Dorset was located in a subtropical marine environment along the margins of the ancient Tethys Ocean. Sediments were deposited in relatively quiet, shallow waters, allowing for exceptional preservation of marine fossils. The Oxford Clay and associated limestone sequences are famous for yielding ammonites in fine detail, alongside other marine creatures such as fish, marine reptiles, and invertebrates.

Collector and Display Appeal

This Cardioceras questicardia ammonite fossil from Dorset is a piece of natural history that combines rarity, beauty, and scientific value. The species’ bold ribbing and elegant shell structure make it highly desirable for fossil enthusiasts and collectors of Jurassic material. Its provenance from the celebrated Jurassic Coast further enhances its significance, linking it directly to one of the most famous fossil localities in the world.

• Type: Fossil Ammonite – Cardioceras questicardia
• Age: Lower Oxfordian, Jurassic (~163–160 million years ago)
• Location: Dorset, United Kingdom
• Scale: Rule squares/cube = 1 cm (see photographs for accurate sizing)
• Authenticity: 100% genuine specimen with Certificate of Authenticity
• Specimen Guarantee: The exact fossil shown in the photographs is the one you will receive

This ammonite offers a fascinating glimpse into the Jurassic seas of Britain and stands as a testament to the rich geological heritage of Dorset. It is both a scientifically valuable specimen and a striking display piece, perfect for collectors, educators, or anyone with a passion for ancient natural history.