Lyelliceras lyelli Ammonite Fossil Rare Albian Cretaceous Chulec Formation Peru COA

Description

Rare Lyelliceras lyelli Ammonite Fossil from Peru

This listing features a rare Lyelliceras lyelli ammonite fossil from the Chulec Formation of the Machay Group, Albian stage of the Cretaceous period, discovered near Proya, Peru. Dating to around 113–100 million years ago, this exceptional specimen captures the beauty and evolutionary importance of one of the most iconic ammonite species of the Cretaceous seas. Each fossil we sell is the actual specimen shown in the photographs and comes with a Certificate of Authenticity, ensuring its provenance and quality.

Geological Context – Chulec Formation, Machay Group

The Chulec Formation of the Machay Group in Peru is one of South America’s most significant Cretaceous fossil-bearing deposits. Formed in shallow marine environments, it is composed mainly of limestones and marls deposited during the Albian stage of the Cretaceous, approximately 110 to 100 million years ago. These marine sediments represent warm, shallow continental shelf seas that supported diverse ecosystems. Ammonites such as Lyelliceras lyelli thrived in these habitats, their remains preserved within the fine-grained sediments that later lithified into stone.

Scientific Classification

• Fossil Type: Ammonite
• Species: Lyelliceras lyelli
• Order: Ammonitida
• Superfamily: Acanthoceratoidea
• Family: Lyelliceratidae
• Geological Age: Albian, Cretaceous (c. 113–100 million years ago)
• Locality: Chulec Formation, Machay Group, Proya, Peru

Morphological Features of Lyelliceras lyelli

Lyelliceras lyelli is a particularly striking ammonite, distinguished by its:

• Robust, involute shell with strong ornamentation.
• Prominent ribs that radiate across the flanks, sometimes developing into tubercle-like nodes.
• Ventral region (venter) marked by continuous ribbing, providing symmetry and structural strength to the shell.
• Suture lines of complex design, reflecting the internal architecture of the shell’s buoyancy chambers.

These features make Lyelliceras a highly desirable genus for collectors, offering both scientific importance and aesthetic appeal. The distinctive ornamentation provides clues about its ecological adaptations and the hydrodynamic properties that allowed these cephalopods to thrive in open marine waters.

Paleoecology and Evolutionary Importance

Ammonites such as Lyelliceras lyelli were nektonic predators, navigating the mid-water zones of the ancient seas using jet propulsion. They preyed upon small fish, crustaceans, and plankton. Their widespread distribution and rapid evolutionary changes make them invaluable index fossils, used to precisely date and correlate Albian-aged marine deposits across different continents.

The Chulec Formation, in particular, is a key stratigraphic unit in South America, with Lyelliceras species serving as important biostratigraphic markers. Fossils from this deposit not only illustrate the evolutionary diversity of ammonites but also provide insights into paleoceanography and marine ecosystems during the mid-Cretaceous greenhouse world.

Collector Value and Authenticity

This specimen of Lyelliceras lyelli represents a genuine and rare ammonite fossil from Peru, a location far less common in the fossil trade than European or North African sources. Its robust shell, characteristic ribbing, and natural preservation make it both scientifically significant and visually striking.

As always, the fossil shown in the photographs is the exact specimen you will receive, pictured with a 1 cm scale cube for reference. It is supplied with a Certificate of Authenticity, guaranteeing that it is a 100% genuine fossil and responsibly sourced.

Key Details

• Fossil: Lyelliceras lyelli Ammonite
• Geological Age: Albian, Cretaceous (c. 113–100 million years ago)
• Formation/Group: Chulec Formation, Machay Group
• Locality: Proya, Peru
• Classification: Order Ammonitida, Family Lyelliceratidae
• Distinctive Features: Strong ribbing, robust shell, complex sutures
• Supplied with Certificate of Authenticity
• Exact specimen shown, with 1 cm scale cube for size reference

A striking and scientifically valuable fossil, this Lyelliceras lyelli ammonite from the Chulec Formation of Peru is a remarkable opportunity to own a rare piece of Cretaceous natural history.