Very Rare Jouaniceras sicardi Ammonite Fossil Santonian Cretaceous Madagascar Genuine Specimen

Description

This listing is for a very rare Jouaniceras sicardi ammonite fossil, dating from the Santonian stage of the Late Cretaceous Period, approximately 86–83 million years ago. Sourced from the world-famous fossil beds of Madagascar, this specimen represents an uncommon and scientifically important ammonite genus, making it a prized find for collectors, researchers, and enthusiasts of natural history.

All of our fossils are 100% genuine specimens and are supplied with a Certificate of Authenticity. The exact fossil shown in the photographs is the one you will receive, with a 1 cm scale cube and rule squares included for accurate size reference.

Geological Context and Age

This ammonite originates from the Santonian stage of the Late Cretaceous, a period when Madagascar was part of the southern Tethys Ocean realm. During this time, the island was surrounded by warm shallow seas that supported diverse ammonite faunas alongside marine reptiles, bivalves, gastropods, and other cephalopods.

The Santonian stage is an important interval in Cretaceous stratigraphy, capturing a time of evolutionary radiation among ammonites. Fossils from Madagascar’s marine deposits are particularly well-preserved, often showing exceptional detail, which allows palaeontologists to use them as reliable index fossils for defining stratigraphic zones.

Morphology and Distinctive Features

Jouaniceras sicardi belongs to the family Collignoniceratidae, within the superfamily Acanthoceratoidea of the order Ammonitida. This family is characterised by robust shells with strong ornamentation, and Jouaniceras is no exception.

The species displays a thick, evolute shell with pronounced ribbing across the flanks. These ribs often connect to ventrolateral tubercles, adding to the shell’s structural strength and distinctive appearance. The ornamentation is a key diagnostic feature, setting Jouaniceras apart from other Santonian ammonites. The morphology suggests a nektonic lifestyle, with this ammonite adapted for swimming in the open water column and functioning as a predator of small marine organisms.

Scientific Importance

The rarity of Jouaniceras sicardi makes it particularly valuable to palaeontologists and collectors alike. Its well-defined morphology helps refine the biozonation of the Santonian stage, contributing to the accurate dating and correlation of Cretaceous rock sequences across the Tethyan region.

As a member of the Collignoniceratidae, Jouaniceras is part of a group of ammonites that underwent significant diversification during the Late Cretaceous. Specimens from Madagascar provide vital insights into the evolutionary history, palaeobiogeography, and ecological roles of these ammonites.

Collector and Display Value

This very rare Jouaniceras sicardi ammonite fossil is a highly desirable specimen for any serious collector. Its scarcity, combined with excellent preservation and clear diagnostic features, makes it an exceptional piece that stands out even in advanced collections.

The fossil’s striking ribbed shell and provenance from Madagascar add both scientific prestige and aesthetic appeal. Displayed in a cabinet or museum setting, it commands attention as both a natural work of art and a key piece of Earth’s Cretaceous history.

Your Guarantee of Authenticity

• 100% genuine Jouaniceras sicardi ammonite fossil from Madagascar
• Geological age: Santonian stage, Late Cretaceous (approx. 86–83 million years old)
• Supplied with a Certificate of Authenticity
• Exact specimen shown in photographs (no stock images)
• Scale cube and rule squares = 1 cm (see photos for accurate sizing)

This Jouaniceras sicardi ammonite fossil is a very rare and scientifically important specimen from Madagascar’s Santonian deposits. With its rarity, striking ornamentation, and guaranteed authenticity, it is an exceptional fossil for collectors of Cretaceous ammonites.