Hildoceras bifrons Fossil Ammonite Jurassic Whitby UK Genuine Runswich Bay Authentic Specimen

Description

Genuine Hildoceras bifrons Fossil Ammonite from Whitby, UK

This superb Hildoceras bifrons fossil ammonite is an authentic specimen from Runswich Bay, near Whitby on the Yorkshire Coast, United Kingdom. Dating back to the Middle Lias of the Lower Jurassic, around 174–182 million years ago, this ammonite is a classic and highly sought-after species. The specimen in the photographs is the exact fossil you will receive, with scale rule squares and a 1 cm cube included for accurate sizing. Every fossil is carefully chosen, guaranteed 100% genuine, and is supplied with a Certificate of Authenticity for complete peace of mind.

Geological Age and Provenance

The ammonite comes from the Middle Lias deposits, specifically the Upper Toarcian stage of the Jurassic period. Runswich Bay and the wider Whitby coastline are world-famous fossil localities, celebrated for their ammonites, marine reptiles, and other Jurassic marine fauna. These rocks were laid down in an ancient shallow sea, part of the larger Tethys Ocean, where fine sediments preserved marine life in extraordinary detail. Fossils from Whitby have long been treasured by both collectors and scientists due to their exceptional preservation and scientific importance.

Species Identification and Classification

Hildoceras bifrons belongs to the order Ammonitida, superfamily Hildoceratoidea, and family Hildoceratidae. It was formally described in the 19th century and remains one of the most iconic Whitby ammonites. The genus Hildoceras is named after Saint Hilda of Whitby, further connecting this fossil to the history and folklore of the region. This species is a key biostratigraphic marker for the Toarcian age, widely used in geological correlation across Europe.

Morphology and Diagnostic Features

The shell of Hildoceras bifrons is typically involute, with tightly coiled whorls and a compressed profile. Strong ribbing runs across the whorls, often branching as it crosses the flanks, giving the ammonite a distinctive and attractive appearance. The ribs terminate at a sharp keel along the venter, which helped stabilize the ammonite in its marine environment. These features make Hildoceras bifrons not only scientifically important but also highly appealing to fossil collectors and enthusiasts.

Palaeoenvironment and Lifestyle

During the Jurassic, Runswich Bay was covered by warm, shallow seas teeming with life. Ammonites such as Hildoceras bifrons were nektonic carnivores, actively swimming and preying on smaller marine organisms. Their hydrodynamic shells enabled efficient movement, while their rapid evolutionary turnover allowed palaeontologists to use them as precise index fossils. The Toarcian stage also coincided with a significant global oceanic event, the Toarcian Oceanic Anoxic Event, which played an important role in shaping marine life and is recorded in the rocks of the Yorkshire coast.

Collector and Scientific Significance

Owning a Hildoceras bifrons from Whitby is to hold a piece of both natural history and regional heritage. These ammonites are prized for their aesthetic ribbed shells, their geological importance as biozone markers, and their connection to the famous Whitby fossil beds. For collectors, they represent one of the most recognisable and desirable Jurassic ammonites from the UK, making them a valuable addition to any collection.

Authenticity and Presentation

This specimen has been carefully selected for quality and clarity, ensuring it represents the species well. The fossil photographed is the exact one you will receive, shown with a 1 cm cube and scale rule for accurate sizing. Every piece is 100% genuine and comes with a Certificate of Authenticity. This Hildoceras bifrons ammonite from Runswich Bay, Whitby, is a striking example of Jurassic life and an exceptional fossil for collectors, educators, and enthusiasts alike.