Fossil Hybodus Shark Spine Reptile Bones Block Aust Cliff Westbury Formation Triassic UK

Description

Genuine Hybodus Shark Spine and Reptile Bones from Aust Cliff

This is a remarkable fossil block containing part of a Hybodus shark spine together with reptile bone fragments, all preserved within the world-famous fish, reptile, and coprolite bed at Aust Cliff, near Bristol, UK. The specimen comes from the Upper Triassic Westbury Formation of the Penarth Group, a classic and scientifically important fossil locality. Fossils from this site provide invaluable insights into the ecosystems of the Late Triassic, and this block is an excellent example combining shark and reptilian remains. The photographs show the exact specimen you will receive, with a 1 cm scale cube for accurate sizing.

Geological Age and Provenance

Dating from the Upper Triassic, around 208–201 million years ago, this specimen originates from the Westbury Formation, part of the Penarth Group. This formation is famous for its vertebrate-rich beds, particularly at Aust Cliff, which has yielded abundant remains of fish, reptiles, and coprolites. Fossils from Aust Cliff have been studied for well over a century and remain an essential reference point for understanding life before the Triassic–Jurassic extinction event. Collectors and researchers alike value specimens from this locality for their rarity, authenticity, and historical importance.

Hybodus Shark Spine

The fossil block includes part of a Hybodus dorsal fin spine. Hybodus was an extinct genus of shark belonging to the order Hybodontiformes, which thrived from the Late Devonian through to the end of the Cretaceous. These sharks were medium-sized predators, easily recognised by their distinctive dorsal spines used for defence against larger predators. The preserved fragment displays the dense, ornamented texture characteristic of Hybodus spines, which were often ridged or covered in small tubercles. Fossilised fin spines provide direct evidence of these ancient sharks, adding a rare and highly collectible feature to this specimen.

Reptile Bones

In addition to the shark material, the block also contains reptile bone fragments, likely representing marine reptiles such as ichthyosaurs or plesiosaurs, which are well known from the Westbury Formation. These bones are larger vertebrate remains that highlight the presence of apex predators within the Triassic seas. The combination of reptile bones and shark remains in one block makes this specimen particularly desirable, as it represents multiple elements of the Late Triassic food web preserved together.

Depositional Environment and Preservation

The Westbury Formation was deposited in a shallow marine to lagoonal setting, where vertebrate remains accumulated in fine sediments. Periods of low oxygen at the seabed prevented decay and scavenging, allowing delicate fossils to be preserved alongside larger skeletal elements. Aust Cliff’s fish, reptile, and coprolite bed is especially famous for preserving fossils in association, giving palaeontologists an unparalleled window into Triassic ecosystems. Fossil blocks such as this one, containing both shark and reptilian remains, illustrate the diversity and complexity of life in these ancient environments.

Discovery and Preparation

This specimen was discovered by our own field team members, Alister and Alison, on the 7th of April 2025 at Aust Cliff. After careful recovery, the fossil block was meticulously cleaned, prepped, and treated by Alison to ensure stability and to enhance the visibility of the natural structures. The preparation process preserved the authentic features of both the shark spine and reptile bones without artificial enhancement, ensuring a fully genuine specimen.

Authenticity and Collectability

All of our fossils are guaranteed 100% genuine specimens and are supplied with a Certificate of Authenticity. Fossil shark spines from Hybodus are highly collectible due to their rarity, and when found in association with reptile bones, they form an exceptional specimen of both scientific and display value. This block from Aust Cliff represents a fascinating part of the Upper Triassic fossil record, making it a standout addition to any private collection, educational display, or museum exhibit. It is a tangible link to the rich marine ecosystems that thrived over 200 million years ago in what is now south-west Britain.