Lobolytoceras siemansi Ammonite Fossil | Toarcian, Jurassic | South Petherton, Ilminster, Somerset UK | Alice Purnell Collection | COA

Description

Fossil Type & Species:

This listing features a genuine fossil of Lobolytoceras siemansi, a distinctive lytoceratid ammonite from the Toarcian Stage of the Early Jurassic Period. This beautifully preserved example was collected from South Petherton near Ilminster in Somerset, England, and is part of the renowned Alice Purnell Collection — a mark of both authenticity and high-quality fossil curation.

Geological Formation & Insight:

Lobolytoceras belongs to the family Lytoceratidae, known for their evolute coiling, broad whorls, and clean, undulating sutures. Unlike heavily ornamented ammonites, Lobolytoceras is characterised by relatively smooth shell morphology with elegant curvature, making it a favourite among collectors for its aesthetic form and rarity.

This specimen dates to the Toarcian Stage of the Early Jurassic, approximately 183 to 174 million years ago, and was preserved in the fossil-rich marine deposits of the Ilminster Basin, a classic UK fossil locality within the Lias Group. During the Early Jurassic, this region was submerged beneath shallow, warm seas teeming with marine life — including ammonites, belemnites, marine reptiles, and bivalves.

These ammonites were fast-swimming nektonic creatures that played a key role in the marine food chain and are now invaluable biostratigraphic markers in geological time studies.

Item Specifics:

• Fossil Type: Ammonite
• Species: Lobolytoceras siemansi
• Geological Age: Toarcian Stage, Early Jurassic (~183–174 million years ago)
• Formation: Lias Group (marine shale and limestone)
• Locality: South Petherton, near Ilminster, Somerset, UK
• Provenance: From the Alice Purnell Collection
• Preservation: Excellent, with visible suture patterns and matrix contrast
• Colour: Natural stone hues (typically grey to beige matrix with dark fossil)
• Size: See scale cube in photo (each square = 1cm)
• Condition: 100% natural, no restoration or repair
• Specimen: You will receive the exact item shown in the photograph

Authenticity Guarantee:

All of our Fossils are 100% Genuine Specimens & come with a Certificate of Authenticity. This piece is professionally sourced and carefully selected, with verifiable provenance from the Alice Purnell Collection, a trusted name in British fossil curation.

Shipping & Packaging:

Your fossil will be securely packaged and shipped with tracking for safe delivery. Ideal for fossil collectors, natural history enthusiasts, educational institutions, or as a unique and scientifically significant gift.

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