RARE Calycoceras picteti Fossil Ammonite – Lower Cenomanian, Cretaceous – Shapwick Grange Dorset UK – COA – Alice Purnell Collection

Description

A rare and scientifically important specimen of Calycoceras picteti, a fossil ammonite from the Lower Cenomanian Stage of the Cretaceous Period, discovered at Shapwick Grange, Dorset, United Kingdom. This exceptional piece is part of the reputable Alice Purnell Collection. The photo displays the exact specimen you will receive—selected for its quality and detail.

Geological Context:

• Species: Calycoceras picteti
• Geological Period: Cretaceous
• Stage: Lower Cenomanian (~100.5 to 96 million years ago)
• Location: Shapwick Grange, Dorset, UK
• Depositional Environment: Shallow marine shelf with chalk-marl deposition during a significant transgressive phase of the Cretaceous greenhouse world; rich in carbonate sediment accumulation

Taxonomic Classification:

• Family: Acanthoceratidae
• Superfamily: Acanthoceratoidea
• Order: Ammonitida
• Suborder: Ammonitina
• Formally Described By: Pictet, 1847

Morphological Features:

Calycoceras picteti is known for its moderately involute shell, with bold, sharp ribbing and regularly spaced tubercles along the flanks and ventrolateral shoulders. These ornamented features made it a well-defended, nektonic swimmer. The prominent ribs bifurcate low on the flanks, often from a small umbilical tubercle, and extend to a nodose keel.

This specimen preserves these features clearly, making it both a visually appealing and taxonomically diagnostic example of mid-Cretaceous ammonites.

Stratigraphic and Scientific Significance:

Calycoceras picteti is a key zonal fossil for the Lower Cenomanian ammonite biozones. Its presence helps correlate marine strata across Western Europe and forms part of the broader picture of ammonite radiation during one of Earth’s major transgressive phases.

This genus is also important for understanding the evolution of ornamented ammonites in the mid-Cretaceous and their response to expanding epicontinental seas.

Additional Details:

• All of our Fossils are 100% Genuine Specimens & come with a Certificate of Authenticity.
• Scale Rule Squares / Cube = 1cm. Please see photo for full specimen sizing.
• From the well-curated and scientifically significant Alice Purnell Collection.

Whether you are a dedicated collector, a palaeontology enthusiast, or a fossil educator, this beautifully preserved Calycoceras picteti is an excellent and rare addition to any serious fossil collection.

Add a true piece of Earth’s ancient marine legacy to your collection today.