Ichthyosaur Jaw Section Fossil Reptile Bone Jurassic Coast Lower Lias Black Ven Lyme Regis

Description

Ichthyosaur Jaw Section Fossil from the Jurassic Coast

This authentic Ichthyosaur Jaw Section Fossil comes from the world-famous fossil beds of Black Ven, Lyme Regis, Dorset, UK, part of the UNESCO-recognised Jurassic Coast. The specimen was discovered by our own field team, Alister and Alison, on 11 November 2025, and has been professionally cleaned, prepared, and stabilised by Alison, ensuring excellent preservation and display quality. The photographs show the actual fossil you will receive, with a 1cm scale cube included for precise size reference. Every fossil we sell is a 100% genuine specimen and comes with a Certificate of Authenticity.

Species Background: Ichthyosauria – Apex Marine Reptiles of the Early Jurassic

Ichthyosaurs belonged to the order Ichthyosauria, a major lineage of highly adapted marine reptiles that thrived throughout the Early Jurassic seas. Their anatomy reflects a life of speed, agility, and predation: streamlined bodies, crescent-shaped tails, elongated snouts, and large, forward-facing eyes suited to hunting in deeper or low-light waters.

The jaw was one of the most important structures in their anatomy. These reptiles possessed long, narrow rostra lined with conical teeth perfect for grasping fast-moving prey such as fish and cephalopods. Even as a partial fragment, this jaw section demonstrates the strength and structural reinforcement necessary for rapid snapping movements and precision feeding. It represents a tangible piece of the skeletal architecture that made ichthyosaurs some of the most accomplished predators of their time.

Geological Provenance: Black Ven Marls, Lower Lias

This fossil originates from the Black Ven Marls, a fossil-rich unit of the Lower Lias deposited during the Hettangian–Sinemurian stages of the Early Jurassic, roughly 196–190 million years ago. These fine-grained marls and mudstones were laid down in a calm, offshore marine basin where limited oxygen levels slowed decomposition and prevented disturbance by scavengers. As a result, the region became one of the most important palaeontological localities in the world.

Black Ven continues to reveal spectacular fossils due to natural erosion along the cliffs. Mary Anning herself famously collected marine reptile remains from this exact area, cementing its historical and scientific significance. Fossils from this deposit typically preserve excellent structural detail, and ichthyosaur jaw sections are among the most desirable finds due to their direct link to the animal’s feeding adaptations.

Morphological Features and Notable Traits

This jaw section displays hallmark ichthyosaur traits, including:

• Curved rostral profile, characteristic of Early Jurassic ichthyosaurs
• Compact, dense bone structure, providing the strength required for powerful biting
• Visible alveolar region, where teeth once anchored into the jaw
• Fine surface texture and linear striations, representing natural bone growth and muscle attachment points

Even in partial form, the fossil offers insight into evolutionary adaptations for underwater hunting. The preserved section illustrates how the jaw tapered forward, forming a long, hydrodynamic snout that reduced drag while swimming.

Depositional Environment and Palaeoecological Importance

During the Early Jurassic, the Lyme Regis coastline lay beneath a warm, shallow epicontinental sea rich in marine life. Ammonites, belemnites, early fish, crustaceans, and other cephalopods formed the backbone of the ecosystem, providing ample prey for ichthyosaurs. The Black Ven Marls accumulated in deeper, quieter parts of this environment, where fine muds settled gently on the sea floor.

The low-oxygen conditions that characterised this depositional setting inhibited decay, allowing bone material—such as this jaw section—to fossilise intact. These geological circumstances make Black Ven one of the best locations for marine reptile fossils globally, and specimens from this area are highly prized for their preservation and scientific significance.

Collector’s Value and Display Appeal

This Ichthyosaur Jaw Section is an exceptional addition to any fossil collection. Its anatomical clarity, locality provenance, and professional preparation make it ideal for collectors, educators, and enthusiasts of palaeontology. The fossil’s natural shape and strong textural details make it visually striking, while its origin from the historic Lyme Regis region lends it additional heritage value.

Whether displayed as part of a marine reptile assemblage or showcased individually, this jaw section offers a fascinating connection to the oceans of the Early Jurassic and the incredible reptiles that inhabited them.

All of our Fossils are 100% Genuine Specimens & come with a Certificate of Authenticity.