Rare Cardioceras excavatus Fossil Ammonite Oxfordian Jurassic Frywald Poland Authentic

Description

Rare Cardioceras excavatus Fossil Ammonite from Poland

Presented here is a rare Cardioceras excavatus ammonite fossil from the Oxfordian Stage of the Late Jurassic, discovered at Frywald, Poland. This outstanding specimen dates back to approximately 163–157 million years ago, a time when shallow seas covered much of Europe, fostering diverse marine ecosystems. The fossil shown in the photographs is the exact specimen you will receive, accompanied by a Certificate of Authenticity, guaranteeing its provenance and quality.

Geological Context

The Oxfordian Stage of the Late Jurassic is renowned for its rich fossil record and the presence of distinctive ammonite faunas. The deposits of Frywald in Poland are part of a classic Jurassic sequence where fine-grained sediments accumulated in a shallow marine environment. These calm depositional conditions allowed for the preservation of ammonite shells in remarkable detail. Specimens such as Cardioceras excavatus are highly sought after not only for their aesthetic qualities but also for their important role in Jurassic biostratigraphy.

Scientific Classification

• Species: Cardioceras excavatus
• Genus: Cardioceras
• Family: Cardioceratidae
• Superfamily: Stephanoceratoidea
• Order: Ammonitida
• Class: Cephalopoda
• Age: Oxfordian Stage, Jurassic (~163–157 million years ago)
• Locality: Frywald, Poland

Morphological Features

The Cardioceras excavatus ammonite is characterised by its moderately involute shell, strongly ribbed whorls, and pronounced ornamentation. The ribs are sharp and distinct, often bifurcating as they cross the flanks before reaching the venter. This ribbing pattern gives the shell a strikingly sculptured appearance, making the species easily recognisable and especially prized by collectors. Its morphology also highlights the evolutionary diversity of Jurassic ammonites, reflecting adaptations to different ecological niches within marine environments.

Stratigraphic and Biozonal Importance

Ammonites of the genus Cardioceras are crucial index fossils for the Oxfordian Stage. Cardioceras excavatus, in particular, is associated with specific ammonite zones that help geologists precisely date and correlate Jurassic rock layers across Europe. Its presence in the fossil record allows researchers to refine the stratigraphy of the Oxfordian seas and understand the palaeobiogeographic distribution of ammonites during this time.

Depositional Environment

During the Oxfordian, Frywald and the surrounding regions were submerged beneath warm, shallow seas. These environments supported abundant ammonite populations along with belemnites, bivalves, brachiopods, fish, and marine reptiles. The fine sediment deposition ensured excellent preservation, capturing the fine ribbing and shell structure of ammonites such as Cardioceras excavatus. Each fossil from this region represents a window into an ancient ecosystem that flourished over 160 million years ago.

Collectible and Scientific Value

This rare Cardioceras excavatus ammonite fossil is not only a visually striking piece of natural history but also a scientifically valuable specimen. It offers collectors, educators, and researchers a tangible connection to the Jurassic seas of Poland. Its rarity, well-defined morphology, and stratigraphic significance make it a desirable acquisition for private collections, display cabinets, or teaching resources in palaeontology.

Item Details

• Type: Fossil Ammonite – Cardioceras excavatus
• Age: Oxfordian, Jurassic (~163–157 million years ago)
• Location: Frywald, Poland
• Notable Features: Distinct ribbing, rare Oxfordian ammonite, index fossil significance
• Scale: Rule squares/cube = 1 cm (see photos for accurate size reference)
• Authenticity: 100% genuine specimen, Certificate of Authenticity included
• Specimen: The exact fossil photographed is the one you will receive

This rare Oxfordian ammonite from Frywald, Poland combines rarity, scientific importance, and natural beauty, making it an exceptional fossil for any serious collector or enthusiast of Earth’s ancient history.