Rare Fossil Ammonite Kosmoceras bigoti Jurassic Callovian St Laon Loudon France COA

Description

Rare Kosmoceras bigoti Ammonite Fossil from St Laon, France

This listing offers a rare Kosmoceras bigoti ammonite fossil, a remarkable specimen from the Callovian Stage of the Middle Jurassic, discovered in the renowned deposits of St Laon, Loudon, France. At approximately 166 to 163 million years old, this ammonite preserves the intricate shell architecture of one of the most distinctive members of the Kosmoceratidae family. Each fossil is a unique, irreplaceable record of ancient marine life, and this is the exact specimen shown in the photographs, measured against a 1 cm scale cube for precise sizing reference.

All of our fossils are 100% genuine specimens and are accompanied by a Certificate of Authenticity, guaranteeing both provenance and scientific value.

Geological Setting – Callovian Stage, Middle Jurassic

The Callovian Stage represents a key interval of the Middle Jurassic, during which much of Europe, including present-day France, was submerged beneath shallow, warm seas. These marine environments supported an extraordinary diversity of ammonites, brachiopods, bivalves, and marine reptiles. Sediments deposited in this time period created the fossil-rich strata of Loudon, France, preserving ammonites like Kosmoceras bigoti in striking detail.

Ammonites from the genus Kosmoceras are crucial to paleontology because they are widely used as index fossils, enabling geologists to correlate and date Jurassic rock layers across Europe. The discovery of Kosmoceras bigoti in St Laon thus holds both scientific and historical significance.

Scientific Classification

• Type: Ammonite Fossil
• Genus: Kosmoceras
• Species: bigoti
• Order: Ammonitida
• Superfamily: Stephanoceratoidea
• Family: Kosmoceratidae
• Age: Callovian, Middle Jurassic (~166–163 million years ago)
• Locality: St Laon, Loudon, France

Morphological Characteristics

This specimen of Kosmoceras bigoti showcases the distinctive features of the genus:

• Shell Form: A moderately involute, coiled shell with a rounded whorl section.
• Ribbing: Strong, radial ribs crossing the flanks and terminating in tubercles.
• Tubercles: Prominent nodules and ornamentation typical of Kosmoceras, enhancing both strength and appearance.
• Suture Pattern: Complex, frilled suture lines indicative of advanced ammonites in the Stephanoceratoidea superfamily.

These features are not only visually striking but also provide insight into the adaptations that enabled ammonites to thrive in Jurassic marine ecosystems.

Paleoecological Significance

Ammonites such as Kosmoceras bigoti played a vital role in the marine food web. They were active predators, likely feeding on small crustaceans, mollusks, and other invertebrates. Their shells, with strong ribbing and tuberculation, suggest adaptations for hydrodynamics and buoyancy control.

At the same time, ammonites themselves were prey for larger marine reptiles like ichthyosaurs and plesiosaurs. The abundance and diversity of ammonites in Callovian seas reflects the rich and dynamic ecosystems of the Middle Jurassic.

Collector Value and Display Appeal

The rarity of Kosmoceras bigoti, combined with its striking shell morphology and provenance from St Laon, Loudon, France, makes this fossil highly desirable for collectors. Its ribbed and tuberculate structure ensures visual appeal, while its scientific importance enhances its value as an educational and display specimen.

Whether displayed in a personal collection, a museum-style case, or as a natural history centerpiece, this ammonite is an authentic and fascinating reminder of the oceans that covered Europe over 160 million years ago.

Key Features

• Species: Kosmoceras bigoti
• Age: Callovian, Middle Jurassic (~166–163 million years ago)
• Origin: St Laon, Loudon, France
• Notable Traits: Ribbed and tuberculate shell, detailed Jurassic morphology
• Authenticity: Guaranteed genuine with Certificate of Authenticity
• Exact Specimen: Item shown in photographs, measured with 1 cm scale cube

This rare Kosmoceras bigoti ammonite fossil is both a scientifically valuable specimen and a beautiful display piece, offering a direct connection to the Jurassic seas of ancient France.