RARE Pseudoschloenbachia (Pseudoschloenbachia) circumperlata Ammonite Fossil Santonian Cretaceous Madagascar

Description

This listing features a rare Pseudoschloenbachia (Pseudoschloenbachia) circumperlata ammonite fossil from the Santonian stage of the Late Cretaceous, discovered in Menbe, Madagascar. Ammonites are extinct cephalopods related to modern squid and cuttlefish, and they are renowned for their coiled shells and intricate suture patterns. This species is particularly notable for its scarcity and the fine preservation of ribbing and shell ornamentation. Each fossil is a unique window into Earth’s prehistoric oceans, representing a lineage that thrived for millions of years before the mass extinction event at the end of the Cretaceous.

All of our fossils are 100% genuine specimens, supplied with a Certificate of Authenticity, ensuring confidence in both scientific accuracy and collectible value.

Geological Age and Stratigraphy

The Santonian stage, dating from approximately 86.3 to 83.6 million years ago, is part of the Late Cretaceous period. This was a time of elevated global sea levels, with large areas of the continents submerged beneath shallow epicontinental seas. In Madagascar, the marine deposits of this age preserved a diverse array of ammonite faunas, including Pseudoschloenbachia, which serve as biostratigraphic markers for the Santonian. These fossils help paleontologists correlate rock sequences across different continents, contributing to our understanding of Earth’s geological history.

Morphological Characteristics

The genus Pseudoschloenbachia is known for its strongly ribbed shells, compressed whorls, and ornate suture lines. The species circumperlata displays pronounced ribbing that sweeps across the flanks and can terminate in tubercles or nodes along the outer whorl. These features are diagnostic for the genus and make this specimen easily identifiable to trained collectors. The shell is planispiral, coiled in a single plane, with ribs and growth lines preserved in fine detail. Such ornamentation likely served both structural and hydrodynamic purposes, strengthening the shell while also influencing how the ammonite navigated its marine environment.

Paleontological Significance

Ammonites like Pseudoschloenbachia circumperlata are invaluable in biostratigraphy, where specific species are used to define fossil zones and identify the relative ages of rock formations. Their rapid evolutionary rates and widespread geographic distribution make them some of the most reliable fossils for dating Cretaceous sediments. Beyond their scientific role, ammonites also hold educational and display value, admired for their natural symmetry and aesthetic appeal. Collectors value rare species such as this for their historical and geological importance as well as their striking appearance.

Depositional Environment and Locality

This specimen was recovered from the Menbe region of Madagascar, an area renowned for its well-preserved Cretaceous marine faunas. During the Santonian, Madagascar was positioned within tropical latitudes, experiencing warm seas teeming with life. The fine-grained sediments in which this ammonite was preserved created excellent fossilisation conditions, allowing intricate shell details to remain intact for over 80 million years.

Collectible Value and Guarantee

• Species: Pseudoschloenbachia (Pseudoschloenbachia) circumperlata
• Age: Santonian stage, Late Cretaceous (~86–83 million years ago)
• Locality: Menbe, Madagascar
• Distinctive ribbing and ornamentation preserved
• Supplied with a Certificate of Authenticity
• Scale cube = 1 cm (see photos for full sizing)
• The exact specimen shown is the one you will receive

This ammonite fossil is an extraordinary addition to any serious fossil collection. With its rarity, detailed preservation, and scientific significance, it embodies both natural beauty and historical importance, making it a prized specimen for collectors, educators, and enthusiasts alike.

Secure this rare Pseudoschloenbachia ammonite fossil today and own a genuine piece of Cretaceous marine history.