Rare Pachystropheus rhaeticus Reptile Humerus Fossil Bone Block Triassic Somerset UK Westbury Formation Specimen Signed COA

Description

Rare Pachystropheus rhaeticus Fossil – Triassic Marine Reptile Humerus Bone Block

Offered here is an exceptional and highly collectible Pachystropheus rhaeticus fossil humerus bone, preserved within a remarkable bone block containing coprolites and additional skeletal fragments. This is a genuinely rare Upper Triassic vertebrate fossil from one of Britain’s most important late Triassic bone-bearing horizons.

The specimen originates from the Westbury Formation, part of the Penarth Group, collected at Blue Anchor, Somerset, England. Fossils of Pachystropheus are scarce, and humerus bones preserved within associated bone beds are especially desirable for serious collectors of prehistoric marine reptiles.

The fossil shown in the photographs is the exact specimen you will receive, with full sizing details clearly visible in the provided images. This piece is a carefully chosen example, selected for both its scientific significance and striking display character.

Included with this fossil is a fully hand-signed Premium Certificate of Authenticity, providing lifetime documentation and confidence in the specimen’s provenance and genuineness.

This specimen was discovered by our own team members, Alister and Alison, on 28 December 2025, and has been professionally cleaned, prepped, and treated by Alison, ensuring excellent presentation and long-term stability.

Geological Setting – Westbury Formation, Penarth Group

This fossil comes from the Westbury Formation, a famous bone-rich unit dating to the Upper Triassic (Rhaetian Stage), approximately 200–205 million years old. This was a critical transitional time in Earth history, just before the Triassic–Jurassic boundary and the rise of Jurassic marine reptile ecosystems.

The Westbury Formation was deposited in shallow coastal marine environments, including lagoons and nearshore seas. These settings accumulated concentrations of bones, teeth, and coprolites, forming fossil bone beds that record a thriving ecosystem of fish, reptiles, and early marine predators.

Blue Anchor is one of the most significant UK localities for these late Triassic fossil assemblages, with rare vertebrate material preserved in dense blocks of ancient seabed sediment.

Fossil Species – Pachystropheus rhaeticus

Pachystropheus rhaeticus is an unusual and rare reptile known from the Late Triassic of England. Often interpreted as a semi-aquatic or coastal marine reptile, Pachystropheus is distinctive for its robust limb bones and unusual skeletal adaptations, suggesting an active lifestyle in shallow marine habitats.

This genus is highly important for understanding reptile evolution at the close of the Triassic, representing part of the diverse fauna that existed shortly before major extinction events reshaped life in the early Jurassic.

Fossil humerus material is uncommon, making this specimen particularly significant as a limb element rather than a more typical isolated fragment.

Bone Block With Coprolites and Associated Remains

This specimen is preserved as a natural bone bed block, containing:

• A partial Pachystropheus humerus
• Additional vertebrate bone fragments
• Fossilised coprolites (prehistoric droppings)

Such blocks provide a rare snapshot of Triassic marine life, capturing not just one fossil but an entire micro-environment of ancient remains. Coprolites add behavioural and ecological importance, offering evidence of feeding relationships within the ecosystem.

Morphology and Preservation Features

The humerus shows the dense structure typical of marine-adapted reptiles, preserved within its original Westbury matrix. Preparation has carefully exposed fossil detail while maintaining the integrity of the surrounding bone bed sediment.

The combination of limb bone, coprolites, and additional fragments makes this a striking specimen for display and serious palaeontological interest.

Provenance, Preparation and Premium Authenticity

This is a 100% genuine Pachystropheus rhaeticus fossil bone block, responsibly collected by Alister and Alison and expertly prepared by Alison.

It includes a hand-signed Premium Certificate of Authenticity, ensuring lifetime provenance and buyer confidence.

Ideal For Serious Collectors and Museum-Grade Displays

This specimen is perfect for:

• Advanced vertebrate fossil collectors
• Triassic marine reptile enthusiasts
• Rare British fossil investors
• Educational and museum-style natural history displays
• Unique deep-time gifts with real discovery provenance

A rare opportunity to own an authentic Pachystropheus rhaeticus humerus fossil in a Triassic bone bed block from Blue Anchor, Somerset, discovered and prepared by our own expert team and accompanied by a premium signed certificate.