Rare Lyelliceras pseudolyelli Ammonite Fossil Albian Cretaceous Chulec Formation Machay Group Proya Peru Genuine Specimen

Description

Rare Lyelliceras pseudolyelli Ammonite Fossil

This listing features a rare Lyelliceras pseudolyelli ammonite fossil, collected from the Chulec Formation of the Machay Group and dating to the Albian Stage of the Cretaceous period. Found in Proya, Peru, this fossil represents one of the classic ammonite forms of the Lower Cretaceous, with its strong ribbing and compact morphology. The exact fossil shown in the photographs is the one you will receive, with a 1 cm cube included for size reference. As with all our pieces, this is a 100% genuine specimen and comes complete with a Certificate of Authenticity.

Geological Age and Context

The Albian Stage (approximately 113–100.5 million years ago) was the last stage of the Early Cretaceous, marked by globally high sea levels and widespread shallow marine environments. During this period, ammonites diversified extensively, producing genera such as Lyelliceras, which are now vital for stratigraphic dating. The Chulec Formation, part of the Machay Group, is composed of fossiliferous marine limestones and shales, deposited in warm shallow seas. Fossils from this formation, especially ammonites, provide important insights into the paleoenvironmental conditions of Cretaceous Peru and the broader South American seaway system.

Taxonomy and Classification

Lyelliceras pseudolyelli is a species of the genus Lyelliceras, belonging to the family Lyelliceratidae, superfamily Acanthoceratoidea, and order Ammonitida. The Lyelliceratidae are well known for their distinctive ribbed shells and evolutionary significance within the Albian. Lyelliceras pseudolyelli is particularly important for paleontology because it serves as a zonal index fossil for parts of the Albian Stage, helping geologists correlate marine deposits across continents. Its close similarity to Lyelliceras lyelli, while displaying subtle differences, makes it an important taxonomic and evolutionary reference species.

Morphological Features

The shell of Lyelliceras pseudolyelli is compact and robust, with strongly ribbed whorls that radiate outward in well-defined, symmetrical patterns. The ribs often strengthen towards the venter and may form subtle nodal points, giving the shell a distinctive textured appearance. The whorls are moderately inflated, giving the ammonite a rounded but sturdy profile. These morphological traits are highly diagnostic and contribute both to its scientific identification and its aesthetic appeal. This specimen clearly exhibits these features, making it a striking display fossil as well as a scientifically valuable reference piece.

Scientific and Collector Importance

As an index fossil, Lyelliceras pseudolyelli plays a central role in biostratigraphy of the Albian Stage. Its short stratigraphic range and easily recognisable shell morphology make it indispensable for dating and correlating marine rocks. For collectors, specimens from the Chulec Formation of Peru are highly sought after due to their rarity and the historical importance of the locality in paleontological research. This fossil offers not only a tangible connection to Early Cretaceous seas but also a beautiful, display-worthy example of ammonite evolution.

Provenance and Authenticity

This specimen was collected in Proya, Peru, from the Chulec Formation of the Machay Group, a globally significant Albian locality. Every fossil we supply is hand-selected, carefully authenticated, and comes with a Certificate of Authenticity. Secure packaging and professional shipping ensure that your specimen arrives safely and in excellent condition, ready for study or display.

This is a rare Lyelliceras pseudolyelli ammonite fossil from the Albian of Peru, combining scientific importance, rarity, and visual appeal. A superb addition to any ammonite, Cretaceous fossil, or natural history collection.