Ichthyosaur Bone Fossil Reptile Black Ven Marls Lower Lias Jurassic Coast Black Ven Lyme Regis Dorset UK

Description

Authentic Ichthyosaur Fossil Bone from the Jurassic Coast

This remarkable Ichthyosaur Fossil Reptile Bone is a genuine specimen from the Black Ven Marls, Lower Lias Formation, found on the world-famous Jurassic Coast at Black Ven, Lyme Regis, Dorset, UK. Dating from the Early Jurassic Period (approximately 195–200 million years ago), this specimen offers a rare and tangible connection to one of the most iconic marine reptiles in Earth’s history.

Your specimen was discovered by our team members, Alister and Alison, on 15 September 2025, and has been carefully cleaned, prepared, and treated by Alison to bring out the finest natural details. The photograph shows the exact fossil you will receive, chosen for its quality and distinctive features.

Geological Context and Origin

This specimen originates from the Black Ven Marls Member of the Charmouth Mudstone Formation, a division of the Lower Lias Group, exposed along the UNESCO World Heritage Jurassic Coast. The cliffs of Lyme Regis and Charmouth are internationally recognised for their exceptional fossil deposits, which include ammonites, belemnites, and the remains of ancient marine reptiles such as Ichthyosaurs, Plesiosaurs, and Pliosaurs.

The Black Ven Marls were deposited in a shallow, low-energy marine environment where fine muds and silts settled on the seabed over millions of years. These sediments accumulated under anoxic (oxygen-poor) conditions, preventing decay and scavenging, and allowing for the preservation of skeletal elements in extraordinary detail. Over geological time, the bone material underwent mineral replacement, typically involving calcite and pyrite, resulting in a beautifully preserved fossil with a subtle natural patina.

This layer corresponds to the Sinemurian Stage of the Early Jurassic and falls within the Arnioceras semicostatum Biozone, a key interval used by geologists for global correlation of Jurassic marine deposits.

Scientific Classification

• Kingdom: Animalia
• Phylum: Chordata
• Class: Reptilia
• Order: Ichthyosauria
• Family: Ichthyosauridae
• Genus: Ichthyosaurus (representative)
• Age: Early Jurassic (Sinemurian Stage)
• Formation: Black Ven Marls, Lower Lias
• Locality: Black Ven, Lyme Regis, Dorset, UK

Ichthyosaurs were not dinosaurs but marine reptiles that evolved from land-dwelling ancestors. They flourished in the oceans of the Mesozoic Era, reaching lengths of up to 10 metres, and are among the best-known fossils from Lyme Regis, famously collected and described by Mary Anning in the early 19th century.

Morphological Features and Preservation

This Ichthyosaur Fossil Bone displays superb preservation with distinct bone texture visible across its surface. The structure reveals a dense, fine-grained internal composition typical of Ichthyosaur skeletal material. Depending on its shape and curvature, this fossil may represent part of a rib, limb, or vertebral element, each critical to understanding the anatomy and biomechanics of these powerful marine predators.

The fossil exhibits a natural grey-brown coloration with subtle mineralised highlights from the Black Ven Marls matrix. Some sections show pyrite mineralisation, a characteristic feature of fossils from this region, adding a metallic sheen in places. The surface texture retains fine biological detail, including faint vascular patterns and growth lines that illustrate the biological nature of the bone.

The scale cube (1 cm) in the photograph provides accurate reference, and full measurements are included in the listing images. The fossil has been professionally stabilised and treated to ensure both structural stability and the preservation of its authentic geological character.

Palaeobiological and Scientific Significance

Ichthyosaurs were fast, streamlined predators that ruled the Jurassic seas, preying on fish, squid, and smaller marine reptiles. Their physiology closely resembled that of modern dolphins, with elongated snouts, large eyes for deep-sea vision, and flexible spines supported by hundreds of precisely shaped vertebrae. Their bones, particularly the dense ribs and limb elements, reflect adaptations for powerful swimming and deep diving.

The preservation of Ichthyosaur bones within the Black Ven Marls provides critical information about early Jurassic marine life and depositional conditions. Each fossil contributes to the understanding of palaeoecology, vertebrate evolution, and taphonomic processes — the stages of decay and fossilisation that occur after death.

Owning such a fossil offers a direct link to an ancient ocean world, where creatures like this Ichthyosaur dominated the seas of what is now southern England nearly 200 million years ago. It embodies both scientific significance and natural artistry, with its intricate structure telling the story of life during the dawn of the Jurassic.

Authenticity and Provenance

All of our fossils are 100% genuine specimens and come complete with a Certificate of Authenticity. Every specimen is responsibly collected, prepared, and treated by our team to ensure ethical sourcing and lasting preservation. The fossil shown in the photographs is the actual specimen you will receive — no replicas, composites, or artificial enhancements are ever used.

This Ichthyosaur Fossil Bone from Black Ven, Lyme Regis, Dorset is a scientifically significant and highly collectible piece from one of the most famous fossil localities in the world. It offers a fascinating glimpse into Britain’s prehistoric seas — a timeless reminder of the marine giants that once swam above the ancient seafloor of the Jurassic Coast.