Rare Kosmoceras (Lobokosmoceras) proniae Iridescent Fossil Ammonite Callovian Jurassic Ryazan Russia with Certificate

Description

Rare Kosmoceras (Lobokosmoceras) proniae Ammonite Fossil from Russia

This listing offers a rare Kosmoceras (Lobokosmoceras) proniae ammonite fossil from the Callovian stage of the Jurassic period, approximately 166 – 163 million years old. Sourced from the well-known fossil deposits of Ryazan, Russia, this remarkable specimen displays natural iridescence, a shimmering nacreous quality that makes it highly desirable for collectors and fossil enthusiasts.

Every fossil we supply is 100% genuine, carefully selected for its preservation and visual appeal, and comes with a Certificate of Authenticity. The photos provided show the exact fossil you will receive, with a 1 cm scale cube included to give a clear size reference.

Geological Age and Formation

This ammonite originates from the Callovian stage of the Middle Jurassic, a time when much of Europe and western Russia was submerged beneath shallow epicontinental seas. These marine environments provided ideal conditions for the fossilisation of ammonites, with fine sediment burial preserving intricate shell details.

Ammonites such as Kosmoceras are of major importance in stratigraphy as index fossils, enabling paleontologists to correlate rock sequences across large regions. The Callovian seas were thriving ecosystems, home to ammonites, belemnites, marine reptiles, and diverse invertebrates, forming a rich and dynamic paleontological record.

Scientific Classification

• Genus: Kosmoceras
• Subgenus: Lobokosmoceras
• Species: Kosmoceras (Lobokosmoceras) proniae
• Order: Ammonitida
• Superfamily: Stephanoceratoidea
• Family: Kosmoceratidae

This placement within the Kosmoceratidae family identifies it as part of a group of ammonites characterised by ornate shell ornamentation and distinctive suture lines. Fossils of Kosmoceras are particularly useful in defining Jurassic biozones and continue to be a focus of paleontological study.

Morphological Features

The Lobokosmoceras proniae ammonite is noted for:

• Strong ribbing across its whorls, giving the shell a robust, textured appearance.
• An evolute shell form, where earlier whorls are prominently visible.
• A complex and detailed suture pattern, typical of Kosmoceratids.
• Preserved iridescent nacre, creating a natural rainbow-like sheen when exposed to light.

This combination of scientific detail and aesthetic beauty makes the fossil both a valuable collector’s item and a natural work of art.

Paleoecology and Lifestyle

Ammonites like Kosmoceras proniae were marine cephalopods, closely related to squid and cuttlefish. Their coiled shells acted as buoyancy devices, allowing them to move vertically within the water column. These predators likely fed on smaller marine organisms such as crustaceans and planktonic life.

The Callovian seas of Russia were home to diverse marine communities, including ichthyosaurs, pliosaurs, bivalves, and gastropods, with ammonites forming an essential part of the food web. This specimen is a tangible remnant of that ancient ecosystem, encapsulating a moment from the Middle Jurassic oceans.

Collector’s Significance

Kosmoceras (Lobokosmoceras) proniae fossils are not only scientifically significant but also highly prized by collectors. The natural iridescence preserved on this specimen enhances its rarity and visual appeal. Its well-defined ribbing and complex sutures make it an outstanding example of its species, appealing to both serious collectors and those seeking a striking display piece.

Owning this ammonite allows you to hold a piece of Earth’s natural history, beautifully preserved for over 160 million years. Its combination of rarity, geological importance, and unique beauty ensures it will stand out in any fossil collection.

Key Details

• Species: Kosmoceras (Lobokosmoceras) proniae
• Age: Jurassic, Callovian (approx. 166 – 163 million years old)
• Origin: Ryazan, Russia
• Family: Kosmoceratidae
• Distinctive Features: Evolute shell, ribbing, complex sutures, iridescent nacre
• Supplied with a Certificate of Authenticity
• The exact fossil pictured is the one you will receive, with a 1 cm scale cube for size reference

This rare fossil is an exceptional addition for any fossil enthusiast, collector, or museum-quality display. It embodies both the scientific richness of the Jurassic seas and the timeless beauty of natural mineralised preservation.