Aegocrioceras varicostatum Heteromorph Ammonite Fossil | Upper Hauterivian, Cretaceous | Hannover Germany | Alice Purnell Collection

Description

Fossil Type & Species:

This listing features a genuine heteromorph ammonite fossil of Aegocrioceras varicostatum, a highly sought-after and unusual ammonite species from the Upper Hauterivian Stage of the Lower Cretaceous Period. Collected in the region of Hannover, Germany, this beautifully preserved specimen is part of the prestigious Alice Purnell Collection, known for its scientifically valuable and expertly curated fossils.

Geological Formation & Insight:

Aegocrioceras is a genus of heteromorph ammonites, members of the group known for their uncoiled or partially uncoiled shells, differing dramatically from the typical planispiral form seen in most ammonites. Aegocrioceras varicostatum is instantly recognisable by its open spiral shape, complex ribbing, and distinctive sculptural features, making it both visually striking and scientifically important.

This specimen was collected from marine strata in the Hauterivian Stage of the Early Cretaceous, dated to approximately 132–129 million years ago. The marine deposits in the Hannover region of northern Germany are part of a well-known sequence of Lower Cretaceous sedimentary rocks that represent an ancient seaway rich in ammonites, belemnites, and marine reptiles.

The preservation in this locality is typically excellent due to fine-grained calcareous mudstones and marls that settled in calm marine conditions, providing a perfect medium for fossilisation. Heteromorph ammonites like Aegocrioceras are of particular interest to paleontologists due to their evolutionary divergence and adaptation strategies.

Item Specifics:

• Fossil Type: Heteromorph Ammonite
• Species: Aegocrioceras varicostatum
• Geological Age: Upper Hauterivian, Lower Cretaceous (~132–129 million years ago)
• Formation: Lower Cretaceous marine sediments
• Locality: Hannover, Germany
• Provenance: From the Alice Purnell Collection
• Preservation: Excellent – showing full heteromorph coiling, strong ribbing, and natural matrix
• Colour: Natural tones – typically grey to brown matrix with contrasting fossil
• Size: See photo – scale rule/cube = 1cm
• Condition: 100% natural; no restoration or enhancement
• Specimen: The exact fossil shown in the photographs is the piece you will receive

Authenticity Guarantee:

All of our Fossils are 100% Genuine Specimens & come with a Certificate of Authenticity. This rare heteromorph ammonite is part of the Alice Purnell Collection, ensuring high scientific and historical value.

Shipping & Packaging:

Your specimen will be securely packaged and shipped with full tracking. A rare and exceptional addition for fossil collectors, natural history enthusiasts, educators, or as a truly unique gift.

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