Kilianella Ammonite Fossil Hauterivian Cretaceous Speeton Clay UK Genuine Certified Specimen

Description

Authentic Kilianella Ammonite Fossil from Speeton, UK

This exceptional Kilianella ammonite fossil comes from the renowned Speeton Clay Formation of Yorkshire, United Kingdom, and dates to the Hauterivian stage of the Early Cretaceous (approximately 132–129 million years ago). Kilianella is a rare and scientifically important genus of ammonites within the family Olcostephanidae, and specimens from Speeton provide vital data for understanding ammonite distribution, stratigraphy, and paleoecology during this stage of Earth’s history. Each specimen we offer is carefully selected, 100% genuine, and comes with a Certificate of Authenticity. The photo provided shows the exact fossil you will receive, with a 1 cm scale cube for reference.

Geological Context – The Speeton Clay Formation

The Speeton Clay Formation is one of the richest Lower Cretaceous fossil deposits in the UK. It is composed of soft, fine clays laid down in a marine shelf environment where ammonites, belemnites, bivalves, and other marine fauna flourished. Conditions in this environment promoted the preservation of delicate shell material, making Speeton one of Europe’s most significant ammonite-bearing localities. The Hauterivian section of the formation is particularly valuable for ammonite biostratigraphy, with Kilianella serving as a marker genus for specific biozones. These fossils help geologists and paleontologists correlate rock sequences across Europe, offering precise dating of the strata.

Scientific Classification

• Class: Cephalopoda
• Subclass: Ammonoidea
• Order: Ammonitida
• Superfamily: Perisphinctoidea
• Family: Olcostephanidae
• Genus: Kilianella

This classification places Kilianella among the perisphinctoid ammonites, a group known for their diverse morphologies and widespread use in stratigraphic correlation. Fossils of this genus are relatively scarce, which enhances their desirability among collectors and researchers.

Morphological Features of Kilianella

Kilianella is characterised by distinctly ribbed shells with relatively evolute coiling, meaning the whorls are not deeply overlapped. The ribs tend to be strong and sharp, sometimes branching and curving gracefully across the outer whorl. These features provide excellent visual contrast and make specimens of this genus immediately recognisable. The shell form reflects adaptations for swimming in the open water column, where buoyancy and mobility were key to survival. The detailed ribbing also provides important clues to paleontologists about evolutionary trends within Early Cretaceous ammonites.

Depositional Environment and Paleoecology

During the Hauterivian stage, northern Europe was dominated by shallow seas that supported diverse marine ecosystems. Ammonites such as Kilianella were nektonic predators, moving actively through the water using jet propulsion. They preyed on planktonic organisms and small crustaceans, playing a crucial role in the food web. Their shells, after death, sank into the fine clays of the seafloor, where rapid burial and oxygen-poor conditions prevented decay and preserved them in extraordinary detail. Fossils from this environment not only represent individual species but also reflect broader patterns of marine life and environmental change in the Early Cretaceous.

Collector and Display Value

This Kilianella ammonite fossil is more than a natural history specimen—it is a rare piece of scientific and geological heritage. Its sharp ribbing, classic ammonite form, and provenance from the Speeton Clay Formation make it highly sought after by collectors worldwide. Such specimens are also valuable for teaching, research, and public display, offering an authentic connection to the oceans of the Early Cretaceous. Whether added to a personal collection, used in an educational context, or displayed as a unique natural artefact, this fossil represents both the beauty and importance of Earth’s deep history.

This carefully chosen ammonite is guaranteed authentic, unique, and irreplaceable, a direct link to a marine world that thrived more than 130 million years ago.