Harpoceras Fossil Ammonite Jurassic Whitby Runswich Bay UK Middle Lias Genuine Specimen

Description

Authentic Harpoceras Fossil Ammonite from Whitby, UK

This listing presents a genuine Harpoceras fossil ammonite from the world-renowned fossil beds of Runswick Bay, Whitby, North Yorkshire, United Kingdom. Carefully selected for its preservation and natural detail, this ammonite is a classic example of the Jurassic marine fauna of Britain’s northern coastline. The photographs provided show the exact fossil you will receive. As with all our specimens, it comes complete with a Certificate of Authenticity, ensuring its provenance and quality.

Geological Timeframe and Formation

This ammonite originates from the Middle Lias (Lower Jurassic) period, dating back approximately 180–174 million years. Specifically, Harpoceras species are associated with the Toarcian Stage, which is famous for rich fossil deposits that document a dynamic period of marine life and climatic change. The Whitby coast and its cliffs, particularly around Runswick Bay, preserve shales and limestone nodules that formed in a shallow epicontinental sea during the Jurassic, with conditions that enabled superb fossil preservation.

Scientific Classification

• Genus: Harpoceras
• Family: Hildoceratidae
• Superfamily: Hildoceratoidea
• Order: Ammonitida
• Class: Cephalopoda
• Age: Middle Lias, Lower Jurassic (Toarcian Stage)
• Locality: Runswick Bay, Whitby, North Yorkshire, UK

Morphological Features

Harpoceras ammonites are easily recognised by their distinctive:

• Compressed, discoidal shells with relatively flat sides.
• Sharp, well-defined keel running along the venter, giving the ammonite a streamlined form.
• Ribbing that tends to be more subdued than other genera such as Dactylioceras, often appearing finer and straighter.
• Sleek morphology adapted for efficient movement through the water, supporting its life as an active nektonic predator.

The elegant coiling and characteristic keel of Harpoceras make it one of the most striking ammonites collected from the Whitby region, prized for both its aesthetic qualities and scientific value.

Stratigraphic and Scientific Importance

Ammonites of the genus Harpoceras are widely used as index fossils for the Toarcian Stage. Their distinctive shell form and restricted stratigraphic distribution allow geologists to accurately date and correlate Jurassic rock layers across Europe and beyond. Fossils like this one are vital for understanding ancient marine ecosystems, palaeoclimate, and evolutionary changes during the Jurassic period.

Palaeoenvironment and Preservation

During the Early Jurassic, the area that is now Whitby was submerged beneath warm, shallow seas. Ammonites such as Harpoceras thrived in these waters, feeding on smaller marine organisms. Upon death, their shells settled onto the seabed, often becoming embedded in fine muds under oxygen-reduced conditions, which inhibited decay and allowed fine structural details to be preserved. Over millions of years, these sediments lithified into shale and limestone, encapsulating ammonites in remarkable condition.

Collector’s Value and Display Potential

This Harpoceras ammonite fossil is an authentic piece of natural history from one of the most celebrated fossil localities in the world. Its sleek, ribbed form and distinctive keel make it a desirable specimen for collectors, educators, and enthusiasts of Jurassic palaeontology. Fossils from Whitby, especially Harpoceras, are highly sought after due to their beauty, scientific significance, and strong connection to the historical fossil-collecting heritage of the Yorkshire coast.

Item Details

• Fossil Type: Ammonite – Harpoceras
• Age: Middle Lias, Lower Jurassic (Toarcian Stage, approx. 180–174 million years)
• Location: Runswick Bay, Whitby, United Kingdom
• Condition: Natural specimen showing distinct coiling, keel, and ribbing features
• Scale: Rule squares/cube = 1 cm (see photos for full sizing)
• Certificate: Supplied with a Certificate of Authenticity
• Specimen Shown: The actual fossil in the photographs is the one you will receive

A classic Harpoceras fossil ammonite from Whitby – an elegant, scientifically important, and visually striking addition to any fossil collection or display.