Fossil Ammonite Indosphinctes petaini Lower Callovian Jurassic Deux Sevres France Authentic Collectors Specimen with COA

Description

This listing is for a genuine fossil ammonite, Indosphinctes petaini, dating from the Lower Callovian stage of the Middle Jurassic (approximately 166–164 million years ago). Found in Deux Sèvres, France, this specimen has been carefully selected for its quality, preservation, and scientific importance. The photographs show the exact specimen you will receive, with scale rule squares / cube = 1 cm for accurate sizing. All of our fossils are 100% genuine specimens and are accompanied by a Certificate of Authenticity.

Geological Context: Lower Callovian of the Jurassic

The Callovian stage is a vital subdivision of the Middle Jurassic, representing an interval where ammonites flourished in shallow seas across Europe. In Deux Sèvres, marine sediments deposited during the Lower Callovian include marls, clays, and limestones that formed in shallow epicontinental seas connected to the Tethys Ocean. These conditions produced exceptional fossil assemblages, particularly ammonites that are used extensively for biostratigraphic correlation.

The Lower Callovian is especially important because of its wealth of diagnostic ammonites, which serve as index fossils. Indosphinctes petaini is one such ammonite, widely used to define specific zones within the Callovian, helping geologists to precisely date and align Jurassic rock sequences.

The Species: Indosphinctes petaini

Indosphinctes petaini belongs to the order Ammonitida, superfamily Perisphinctoidea, and family Perisphinctidae. Ammonites within this genus are renowned for their robust and ornamented shells. The species I. petaini is particularly recognisable for its planispiral coiling, strong ribbing, and bifurcating ribs that extend across compressed whorls.

This species was a nektonic predator, actively swimming in Jurassic seas and feeding on small marine organisms. Its morphological traits suggest adaptations for efficient buoyancy and mobility, giving it an advantage as a predator in open waters. The distinctive ribbing also provides crucial taxonomic features, allowing paleontologists to easily identify the species within Callovian fossil assemblages.

Morphological and Scientific Features

• Order: Ammonitida
• Superfamily: Perisphinctoidea
• Family: Perisphinctidae
• Genus and Species: Indosphinctes petaini
• Geological Stage: Lower Callovian, Middle Jurassic (c. 166–164 Ma)
• Locality: Deux Sèvres, France
• Shell Traits: Planispiral form, strong ribbing, bifurcating ribs, compressed whorls
• Scientific Significance: Important index fossil used for Callovian biozones and Jurassic stratigraphy

The striking ornamentation and diagnostic ribbing patterns of Indosphinctes petaini make it both a scientifically valuable ammonite and a visually appealing specimen for collectors.

Collector and Display Value

This ammonite is not only a piece of paleontological significance but also a highly collectible display fossil. Its bold ribbing and elegant coiling highlight the natural beauty of ammonite shells, while its provenance from Deux Sèvres, France, makes it an especially desirable specimen.

Indosphinctes petaini fossils from this region are highly regarded by both collectors and researchers, as they combine aesthetic appeal with scientific importance. For private collections, educational purposes, or display, this ammonite offers a tangible connection to the marine ecosystems of the Jurassic seas.

All of our fossils are carefully chosen for authenticity and quality, and each is supplied with a Certificate of Authenticity. This Indosphinctes petaini ammonite represents a unique opportunity to own a genuine specimen of Middle Jurassic heritage from one of Europe’s most important fossil localities.