Rare Platypleuroceras brevispina Ammonite Fossil Genuine Jurassic Upper Pliensbachian St Peters Field Radstock UK with COA

Description

100% Genuine Rare Platypleuroceras brevispina Ammonite Fossil

This listing is for a rare Platypleuroceras brevispina ammonite fossil from the Upper Pliensbachian stage of the Jurassic period, discovered at St Peters Field, Radstock, United Kingdom. The specimen pictured is the exact fossil you will receive, with a 1cm scale cube included in the photo for accurate size reference. Every fossil is 100% genuine and supplied with a Certificate of Authenticity, guaranteeing its authenticity and provenance.

Geological Background – Upper Pliensbachian, Jurassic

The ammonite comes from the Upper Pliensbachian stage of the Early Jurassic, dating to approximately 185 million years ago. During this time, southern Britain was submerged beneath shallow, warm epicontinental seas. Fine-grained mudstones and limestones were deposited across the region, creating the famous Lower Lias sequence that preserves an extraordinary diversity of marine life.

St Peters Field at Radstock, Somerset, is a key fossil locality in the UK, yielding rare ammonites from the Spinatum Zone of the Upper Pliensbachian. Fossils from this zone are essential for defining Jurassic biozones and for correlating marine deposits across Europe, giving specimens from this site both scientific and collector significance.

Fossil Type and Species – Platypleuroceras brevispina

Platypleuroceras brevispina belongs to the order Ammonitida, superfamily Eoderoceratoidea, and family Pleuroceratidae. Ammonites in this genus are particularly notable for their strong ribbing and spined morphology, which make them highly distinctive among Early Jurassic ammonites.

These ammonites were nektonic carnivores, actively swimming and feeding on smaller marine organisms in Jurassic seas. Their chambered shells provided buoyancy regulation, while their ribbing and spines may have served both hydrodynamic and defensive functions.

Morphology and Distinguishing Features

The shell of Platypleuroceras brevispina is evolute, meaning the whorls are not tightly coiled, leaving the earlier whorls visible. It is strongly ornamented with ribs that frequently terminate in spines or short projections along the ventrolateral shoulder – a hallmark feature of this species.

The ribs are sharp and well defined, often bifurcating as they cross the flanks, producing a strikingly sculptured appearance. The short spines give the shell its name “brevispina,” meaning “short-spined.” Suture lines are complex and deeply folded, consistent with ammonites of this age and group.

Biozone and Scientific Importance

Platypleuroceras brevispina is associated with the Spinatum Zone of the Upper Pliensbachian, one of the key ammonite biozones used for biostratigraphic correlation of Jurassic rocks across Europe. This makes the species both scientifically important and highly valuable to collectors of index fossils.

As a rare ammonite in British deposits, specimens of this species are prized for their scarcity, distinctive morphology, and role in stratigraphy. They provide insight into ammonite evolution during a dynamic interval of the Early Jurassic seas.

Collectors and Enthusiasts

For fossil collectors, a Platypleuroceras brevispina ammonite fossil from St Peters Field, Radstock, represents a particularly desirable addition. Its rarity, combined with its striking ribbing and spination, make it stand out among ammonites of the Lower Lias. With its well-documented provenance and scientific value, this specimen is an excellent choice for both serious collectors and enthusiasts of Jurassic fossils.

Why This Specimen is Unique

• Rare Platypleuroceras brevispina ammonite fossil
• From the Upper Pliensbachian, Spinatum Zone (~185 million years old)
• Collected at St Peters Field, Radstock, United Kingdom
• Supplied with a Certificate of Authenticity
• Exact fossil shown in the photo will be sent
• Includes 1cm cube for accurate size reference

This rare Platypleuroceras brevispina ammonite fossil from Radstock is a scientifically valuable and visually distinctive specimen. With its strong ribbing, spined morphology, and rarity, it represents a superb addition to any collection of Jurassic ammonites or British fossil treasures.