Pentacrinites Crinoid Fossil Slab Jurassic Lyme Regis Dorset UK Black Ven Marls Specimen

Description

Pentacrinites Crinoid Fossil Slab from the Jurassic Coast, Lyme Regis

This impressive fossil slab contains Pentacrinites sp. crinoid remains, preserved within the famous Black Ven Marls of the Lower Lias Formation, collected from the world-renowned fossil locality of Black Ven, Lyme Regis, Dorset, United Kingdom. These deposits form part of the Jurassic Coast UNESCO World Heritage Site, one of the most important fossil-bearing coastlines in the world.

Dating to the Early Jurassic Period (approximately 201–174 million years ago), this specimen preserves the remains of ancient marine echinoderms that lived on the seabed of a shallow Jurassic sea. The fossil shown in the photographs is the exact specimen you will receive, carefully selected for its natural preservation and fossil detail.

This genuine fossil specimen includes a fully hand-signed Premium Certificate of Authenticity, confirming the specimen’s legitimacy and provenance.

Full sizing of the fossil can be seen in the listing photographs.

Geological Origin – Black Ven Marls, Lower Lias Formation

The fossil originates from the Black Ven Marls, part of the Lower Lias Group, which forms the cliffs around Lyme Regis along the Dorset coast. These rocks were deposited during the Early Jurassic, specifically within the Hettangian to Sinemurian stages, when the region was covered by a warm, shallow epicontinental sea.

The sediments consist mainly of dark marine mudstones and marls, deposited in relatively calm offshore conditions. Periodic low-oxygen environments on the seabed helped preserve delicate marine organisms, allowing fossils such as crinoids, ammonites, bivalves, and marine reptiles to be preserved with remarkable detail.

Black Ven is one of the most historically significant fossil sites in the world and was famously explored by pioneering fossil collector Mary Anning, whose discoveries helped shape early palaeontology.

About Pentacrinites – Jurassic Sea Lilies

The genus Pentacrinites belongs to a group of marine echinoderms known as crinoids, commonly called sea lilies. Despite their plant-like appearance, crinoids are animals related to modern starfish, sea urchins, and brittle stars.

Taxonomic classification:

• Phylum: Echinodermata
• Class: Crinoidea
• Order: Isocrinida
• Family: Pentacrinitidae
• Genus: Pentacrinites

Pentacrinites were stalked crinoids, meaning they anchored themselves to the seafloor using a long segmented stem. At the top of the stem sat a crown composed of feathery arms used to filter microscopic food particles from the surrounding seawater.

These animals were highly abundant in Jurassic seas and often formed dense colonies across the seabed.

Morphology and Fossil Preservation

Pentacrinites fossils are recognised by their distinct pentagonal stem segments, known as columnals, which form the long stalk supporting the animal’s crown. These segments often occur in articulated chains or scattered across slabs of sedimentary rock.

Key features typically visible in Pentacrinites fossils include:

• Pentagonal stem columnals stacked to form the stalk
• Radial symmetry typical of echinoderms
• Occasionally preserved branching arms or cirri used for feeding and attachment
• Distinct joint surfaces between stem segments

When these animals died or were disturbed by storms, the delicate skeleton often disarticulated, scattering the columnals across the seafloor. Rapid burial in fine sediment preserved these remains within the marl layers that now form the cliffs at Black Ven.

This fossil slab captures a natural accumulation of crinoid skeletal elements, providing a fascinating glimpse into Jurassic marine life.

Early Jurassic Marine Ecosystem

During the Early Jurassic, the seas surrounding what is now southern England were rich in marine biodiversity. The seabed around Lyme Regis supported a wide range of organisms including:

• Ammonites
• Belemnites
• Bivalves
• Marine reptiles such as ichthyosaurs and plesiosaurs
• Echinoderms including crinoids like Pentacrinites

Crinoids such as Pentacrinites thrived in these environments by filter-feeding on plankton and organic particles, extending their feathery arms into the currents to capture food.

Storm events and changing sediment conditions periodically buried these organisms, allowing their skeletons to become preserved within the Jurassic sediments.

Authentic Jurassic Coast Fossil Specimen

This fossil slab represents an excellent example of Jurassic echinoderm fossils from one of the most famous fossil localities in the world. Specimens from the Lyme Regis coastline are highly sought after due to their scientific significance and historical connection to the early development of palaeontology.

Key features of this specimen:

• Genuine Pentacrinites sp. crinoid fossil slab
• From the Black Ven Marls, Lower Lias Formation
• Collected at Black Ven, Lyme Regis, Dorset, UK
• Photographs show the exact fossil specimen you will receive
• Supplied with a fully hand-signed Premium Certificate of Authenticity

This remarkable fossil makes an outstanding addition to Jurassic fossil collections, crinoid displays, educational collections, or natural history enthusiasts interested in the ancient seas of the Jurassic Coast.