Rare Crioceratites duvali Heteromorph Fossil Ammonite Hauterivian Cretaceous Drome Gap France Authentic Collector Specimen with COA

Description

This listing offers a rare fossil ammonite, Crioceratites duvali, a striking heteromorph ammonite from the Hauterivian stage of the Early Cretaceous (approximately 132–129 million years ago). Sourced from the renowned Drôme and Gap regions of southeastern France, this specimen is an outstanding example of the unusual, uncoiled shell morphology that defines heteromorph ammonites. The fossil shown in the photographs is the exact piece you will receive, displayed alongside a scale cube = 1 cm for accurate size reference. Every specimen is 100% genuine and supplied with a Certificate of Authenticity.

Geological Context: Hauterivian, Early Cretaceous

During the Hauterivian stage, much of southern France lay beneath shallow seas along the margins of the ancient Tethys Ocean. These warm marine environments provided the ideal conditions for ammonites to flourish, leaving behind richly fossiliferous layers of marl, limestone, and clay.

The Drôme and Gap localities are internationally celebrated for their exceptionally preserved ammonites, particularly heteromorph species. Ammonites such as Crioceratites duvali serve as index fossils, enabling geologists to precisely date Hauterivian strata and establish reliable biozones for Early Cretaceous stratigraphy. Their distinctive morphology adds further value, making them important for evolutionary studies of ammonite diversification.

The Species: Crioceratites duvali

Crioceratites duvali belongs to the order Ammonitida, superfamily Ancylocerataceae, and family Ancyloceratidae. This heteromorph ammonite differs from typical ammonites by having a loosely coiled, crioconic shell. Instead of forming a tightly wound spiral, the whorls are open and separated, giving it an unusual and eye-catching appearance.

The shell is ornamented with strong ribbing that crosses the flanks and outer surface, sometimes accompanied by subtle tuberculation, which enhances its striking three-dimensional form. The open coil and structural features suggest a different ecological strategy compared to standard planispiral ammonites—possibly involving a slower, drifting lifestyle in the water column.

These distinctive traits make C. duvali a key fossil for paleontologists studying the diversity of heteromorph ammonites during the Early Cretaceous.

Morphological and Scientific Features

• Order: Ammonitida
• Superfamily: Ancylocerataceae
• Family: Ancyloceratidae
• Genus and Species: Crioceratites duvali
• Geological Stage: Hauterivian, Early Cretaceous (c. 132–129 Ma)
• Locality: Drôme and Gap, France
• Shell Traits: Loosely coiled crioconic form, strong ribbing, distinctive open whorls
• Scientific Importance: Index fossil for Hauterivian deposits, important for evolutionary and biostratigraphic studies

Collector and Display Value

Heteromorph ammonites are considerably rarer than their tightly coiled relatives, and Crioceratites duvali is one of the most fascinating examples from the Hauterivian. Its distinctive open coiling and strong ribbing make it a visually arresting piece that is equally valuable for scientific study and private display.

The provenance from Drôme and Gap, France, adds to its prestige, as these regions are among the world’s best-known localities for Early Cretaceous ammonite fossils. Collectors value such specimens for their rarity, scientific significance, and aesthetic appeal.

This Crioceratites duvali specimen is carefully chosen for quality and preservation. Supplied with a Certificate of Authenticity, it represents a rare opportunity to own a genuine heteromorph ammonite from the Hauterivian seas of France—an extraordinary addition to any serious fossil collection.