Rare Mariella oechlerti Heteromorph Fossil Ammonite Lower Cenomanian Cretaceous Cher France with COA

Description

Rare Mariella oechlerti Heteromorph Ammonite from Cher, France

This specimen is a rare Mariella oechlerti heteromorph fossil ammonite, collected from the Lower Cenomanian deposits of Cher, France. Dating to the Late Cretaceous Period, approximately 100–94 million years ago, this ammonite belongs to a remarkable group of heteromorphs that abandoned the flat spiral coil of traditional ammonites in favour of complex, irregular shell morphologies. Fossils of Mariella oechlerti are highly desirable due to their rarity, scientific value, and striking display qualities.

Every specimen we supply is 100% genuine and comes with a Certificate of Authenticity. The photographs show the exact fossil you will receive, with a 1cm scale cube and rule squares included for accurate sizing.

Geological Age and Locality

The fossil originates from the Lower Cenomanian Stage, the earliest stage of the Late Cretaceous. This was a time of dramatic environmental changes when global sea levels were some of the highest in Earth’s history. Vast epicontinental seas covered much of Europe, creating rich marine habitats that supported a wide diversity of ammonites and other marine organisms.

The Cher region of France is internationally recognised for its Cretaceous fossil sites, with ammonites such as Mariella oechlerti serving as key index fossils. The locality is significant not only for its abundance of heteromorph ammonites but also for its contribution to the refinement of Cretaceous biostratigraphy.

Fossil Type and Scientific Classification

• Genus: Mariella
• Species: Mariella oechlerti
• Order: Ammonitida
• Superfamily: Turrilitoidea
• Family: Turrilitidae

Mariella oechlerti is a classic index fossil of the Lower Cenomanian, used by geologists to identify and correlate rock layers across Europe. Its restricted stratigraphic distribution makes it particularly important for pinpointing precise horizons in the fossil record.

Morphological Features

This species is easily recognised by its distinctive heteromorph shell form and diagnostic ornamentation:

• Uncoiled to Partially Coiled Shell: Instead of forming a flat spiral, the shell develops in irregular, helically curved whorls.
• Strong Ribbing: Bold ribs cross the flanks, often branching and sometimes ornamented with tubercles.
• Tubercles and Nodes: These features add to the distinctive ornamentation, aiding in species-level identification.
• Keel Development: Many specimens show keel-like features along the venter, contributing to the shell’s structural form.

These traits combine to make Mariella oechlerti both visually striking and scientifically distinctive.

Scientific and Collector Importance

As a heteromorph ammonite with a restricted range, Mariella oechlerti plays a vital role in Cenomanian biostratigraphy. Its presence in deposits provides a reliable marker for Lower Cenomanian strata, making it crucial for correlating sites across Europe.

Collectors prize Mariella oechlerti not only for its rarity but also for its unusual morphology, which contrasts strongly with the more familiar planispiral ammonites. Well-preserved specimens from Cher are especially sought after due to their provenance from one of France’s most important fossil localities.

Display and Educational Value

This fossil has been carefully selected for its quality and distinctive heteromorph form. It is both a visually compelling display specimen and a scientifically valuable ammonite that demonstrates the evolutionary diversity of the Cretaceous seas.

Ideal for private collectors, educational institutions, or museums, this rare Mariella oechlerti ammonite from Cher, France represents a significant piece of natural history. It captures the fascinating evolutionary experiments of heteromorph ammonites and offers a unique opportunity to own a genuine Lower Cenomanian fossil with outstanding provenance.