Hildoceras semipolitum Ammonite Fossil Lower Toarcian Jurassic Lozere France Genuine Specimen

Description

Authentic Hildoceras semipolitum Ammonite Fossil from Lozère, France

This fine specimen of Hildoceras semipolitum ammonite fossil originates from the Lower Toarcian stage of the Early Jurassic, approximately 182 million years ago, and was discovered in the fossil-rich deposits of Lozère, France. Ammonites of this species are highly prized by collectors and researchers alike for their distinctive morphology, their biostratigraphic importance, and their role in reconstructing Jurassic marine ecosystems. Each fossil offered is individually selected, photographed accurately, and supplied with a Certificate of Authenticity, guaranteeing its genuine nature and provenance.

Geological Age and Depositional Environment

The Toarcian stage is a key interval within the Jurassic system, spanning from about 182 to 174 million years ago. This particular ammonite comes from the Lower Toarcian, a time when Western Europe was covered by warm, shallow seas connected to the Tethys Ocean. Sediments in Lozère typically consist of fine-grained marls and limestones that reflect deposition in calm marine shelf environments. These conditions allowed excellent preservation of ammonite shells, often retaining exquisite morphological detail.

The Lower Toarcian is also famous for the Toarcian Oceanic Anoxic Event (T-OAE), a period of widespread low-oxygen conditions that dramatically impacted marine life. Fossils from this interval offer insights into how ancient ecosystems adapted to major climatic and environmental changes.

Scientific Classification

• Class: Cephalopoda
• Subclass: Ammonoidea
• Order: Ammonitida
• Superfamily: Hildoceratoidea
• Family: Hildoceratidae
• Genus: Hildoceras
• Species: Hildoceras semipolitum

Ammonites of the genus Hildoceras are characteristic index fossils for the Lower Toarcian stage and are frequently used by paleontologists to date and correlate sedimentary layers across Europe. Their distinctive shell forms make them instantly recognisable and highly collectable.

Morphological Features and Distinctive Traits

This specimen of Hildoceras semipolitum shows the defining features of the species: a moderately involute shell with compressed whorls, strong ribbing across the flanks, and an elegant coiling pattern that produces a refined, streamlined profile. The ribs typically cross the venter in a slightly curved manner, enhancing the ornamental appearance of the shell. The sutures are highly intricate and folded, characteristic of Jurassic ammonites, and contribute to the fossil’s scientific and visual appeal.

The morphology of Hildoceras suggests an active nektonic lifestyle. These ammonites were likely fast swimmers in the open seas, preying upon plankton, crustaceans, and small mollusks. Their evolutionary adaptations reflect both ecological versatility and sensitivity to environmental shifts, which is why they are such reliable biostratigraphic markers.

Paleoecological and Evolutionary Importance

The Hildoceratidae family represents one of the most significant ammonite groups of the Early Jurassic. Their abundance and rapid evolutionary changes provide paleontologists with precise tools for reconstructing geological timescales. Fossils of Hildoceras semipolitum are especially important in establishing zones within the Lower Toarcian, making them vital in the study of Jurassic stratigraphy.

In addition to their scientific role, these fossils also provide a glimpse into the biodiversity of the Early Jurassic seas of Europe. Lozère, with its fine preservation conditions, remains one of the classic localities for Toarcian ammonites, supplying specimens that are valued worldwide by both museums and private collectors.

Collector and Display Value

This Hildoceras semipolitum ammonite fossil from France combines scientific importance with natural beauty. Its well-defined ribbing, elegant shape, and excellent preservation make it both an attractive display piece and a specimen of research value. Whether you are an advanced fossil collector, a geologist, or someone with a passion for natural history, this ammonite provides a tangible connection to life in the Jurassic seas nearly 182 million years ago.

Every fossil is supplied with a Certificate of Authenticity and is the exact specimen shown in the photographs, complete with scale reference for sizing. This ensures you are investing in a genuine and carefully chosen piece of Earth’s ancient history.