Rare Catasigaloceras planicerclus Ammonite Fossil Kellaways Rock Jurassic Humberside UK

Description

Rare Catasigaloceras planicerclus Ammonite Fossil – Jurassic of Humberside, UK

This listing is for a rare Catasigaloceras planicerclus ammonite fossil, collected from the Kellaways Rock of the Lower Callovian Stage, Middle Jurassic, in Humberside, United Kingdom. A carefully selected specimen, this ammonite displays the distinct features of the species and is supplied with a Certificate of Authenticity. The photographs provided show the exact specimen you will receive, with a 1 cm scale cube included for accurate size reference.

Geological Age and Provenance

This fossil originates from the Lower Callovian Stage (around 166–164 million years ago), part of the Middle Jurassic period. The Kellaways Rock, a well-known formation within the Jurassic sequence of Britain, has yielded an abundance of marine fossils, particularly ammonites. These strata represent deposits from shallow seas that once covered much of England, providing an ideal environment for ammonites and other marine organisms to thrive. Fossils from Humberside are considered both scientifically important and historically significant, reflecting Britain’s rich geological heritage.

Scientific Classification

• Kingdom: Animalia
• Phylum: Mollusca
• Class: Cephalopoda
• Order: Ammonitida
• Superfamily: Stephanoceratoidea
• Family: Stephanoceratidae
• Genus: Catasigaloceras
• Species: Catasigaloceras planicerclus

The genus Catasigaloceras belongs to the Stephanoceratidae, a family of ammonites renowned for their ornate ribbing and importance in Jurassic biostratigraphy. This species is considered a marker for the Lower Callovian, making it highly significant for paleontological research.

Morphological Features

*Catasigaloceras planicerclus* is noted for its moderately involute shell and characteristic ribbing. The ribs are strong, sharp, and typically bifurcate or branch across the flanks before curving onto the venter. The whorls are compressed yet robust, with the ornamentation creating a striking appearance. The shell structure reflects adaptations that combined hydrodynamic efficiency with strength, vital for survival in Jurassic marine environments.

The ribbing and coiling patterns of this species also allow paleontologists to easily distinguish it from other closely related ammonites, further cementing its value as a biostratigraphic index fossil for the Callovian.

Paleoenvironment and Importance

During the Callovian, the Humberside region lay beneath shallow, nutrient-rich seas connected to broader epicontinental marine systems across Europe. These environments supported diverse marine life, from ammonites and belemnites to marine reptiles. Ammonites such as Catasigaloceras planicerclus were important predators and prey within this ecosystem, contributing to the dynamic food chain of the Jurassic seas.

In geology, Catasigaloceras is particularly valuable for defining biozones within the Callovian, enabling detailed stratigraphic correlations across the United Kingdom and beyond. Specimens like this one are indispensable to both scientific study and serious fossil collections.

Collector and Display Value

This rare ammonite fossil represents an outstanding addition to any collection, combining visual appeal with scientific importance. Its bold ribbing, robust whorl form, and provenance from Humberside’s Kellaways Rock make it both an impressive display piece and a valuable research specimen. Collectors of British ammonites, students of paleontology, and enthusiasts of Jurassic geology will all appreciate the uniqueness and rarity of this fossil.

Key Features

• Species: Catasigaloceras planicerclus, a rare ammonite from the Callovian.
• Provenance: Kellaways Rock, Lower Callovian, Jurassic of Humberside, UK.
• Distinctive ribbing and compressed shell form.
• Significant index fossil used in Jurassic biostratigraphy.
• Supplied with a Certificate of Authenticity.

This Catasigaloceras planicerclus ammonite fossil is a scientifically significant and visually striking specimen, offering collectors the chance to own a genuine piece of Jurassic history from the fossil-rich deposits of Britain.