Description
Porpoceras fibulatum Fossil Ammonite from Whitby, United Kingdom
This listing is for a Porpoceras fibulatum fossil ammonite, a rare and scientifically significant specimen from the Lower Toarcian stage of the Jurassic period. Discovered in Whitby, North Yorkshire, United Kingdom, this ammonite is part of the famous Whitby Mudstone Formation, a world-renowned source of Early Jurassic fossils. The photographs show the exact specimen you will receive, with a 1 cm scale cube included for accurate sizing. Every fossil we sell is 100% genuine and is supplied with a Certificate of Authenticity.
Geological Age and Setting – Lower Toarcian, Jurassic
This ammonite dates to the Lower Toarcian stage, approximately 182–174 million years ago. During this time, the Whitby area lay beneath shallow seas connected to the northern margin of the Tethys Ocean. Fine-grained shales and mudstones were deposited in low-oxygen marine environments, creating exceptional conditions for fossil preservation.
The Toarcian stage is globally significant due to the Toarcian Oceanic Anoxic Event (T-OAE), a major climatic and environmental episode that shaped marine ecosystems. Ammonites like Porpoceras fibulatum are essential for understanding the biodiversity and stratigraphy of this critical interval in Earth’s history.
Species and Classification
- Genus: Porpoceras
- Species: fibulatum
- Order: Ammonitida
- Superfamily: Hildoceratoidea
- Family: Hildoceratidae
Porpoceras fibulatum belongs to the Hildoceratidae, a family of ammonites known for their ornate ribbing and evolutionary importance during the Toarcian. This genus is closely related to the previously classified Peronoceras and remains a key taxon in ammonite biostratigraphy.
Morphological Features
The Porpoceras fibulatum ammonite is easily identified by several striking features:
- Shell form: Evolute, with inner whorls exposed.
- Ribbing: Bold ribs crossing the flanks, often bifurcating, giving the shell a distinctive ornamented appearance.
- Whorl profile: Robust and rounded, adding strength and symmetry to the overall form.
- Ornamentation: Occasional nodal features along the ribs enhance the shell’s texture and visual impact.
- Sutures: Intricate suture lines add detail and are characteristic of Hildoceratidae ammonites.
These features not only provide important taxonomic detail but also make the fossil a visually impressive display specimen.
Stratigraphy and Biozone Importance
Porpoceras fibulatum is a critical index fossil within the Lower Toarcian ammonite zones. Its occurrence in the Whitby Mudstone Formation allows geologists to refine stratigraphic frameworks and correlate marine deposits across Europe. As such, it has both scientific and collector value, helping to reconstruct the evolutionary history of ammonites during the Early Jurassic.
Collector and Scientific Value
- Collectors will appreciate this specimen for its rarity, strong ribbing, and provenance from Whitby, one of the world’s most celebrated fossil localities.
- Researchers and educators prize it as a key stratigraphic marker species, useful in defining Toarcian ammonite biozones.
- For display, its bold ornamentation and excellent preservation make it a beautiful and eye-catching specimen, ideal for any collection.
Authenticity and Guarantee
All of our fossils are responsibly sourced and are 100% genuine specimens. This Porpoceras fibulatum fossil ammonite has been carefully selected for its preservation, rarity, and quality. Each fossil is accompanied by a Certificate of Authenticity, providing complete assurance of its provenance.
Key Information at a Glance
- Fossil Type: Ammonite
- Species: Porpoceras fibulatum
- Geological Age: Lower Toarcian, Jurassic (~182–174 million years old)
- Locality: Whitby, North Yorkshire, United Kingdom
- Family: Hildoceratidae
- Order: Ammonitida
- Condition: Natural fossil with bold ribbing and excellent preservation
- Authenticity: Guaranteed with Certificate of Authenticity
This Porpoceras fibulatum ammonite fossil from Whitby is both a scientifically important specimen and a visually striking addition to any fossil collection, making it ideal for collectors, researchers, and enthusiasts of Britain’s Jurassic heritage.





Reviews
There are no reviews yet.