Fossil Ammonite 4″ Skirroceras leptogyrale, Jurassic, Middle Toarcian, Somerset UK, Genuine Specimen with COA

Description

Offered for sale is a Fossil Ammonite of Skirroceras leptogyrale measuring approximately 4 inches, from the Middle Toarcian Stage of the Jurassic Period, found in Somerset, United Kingdom. This is a highly attractive and scientifically relevant ammonite species, recognised for its finely detailed morphology and biostratigraphic value.

The specimen shown in the photographs is the actual item you will receive, professionally selected for its preservation and display quality.

Scale Rule Squares / Cube = 1cm — please refer to the images for full sizing.

Key Geological and Scientific Information:

• Species: Skirroceras leptogyrale
• Fossil Type: Ammonite (extinct marine cephalopod)
• Geological Period: Jurassic
• Geological Stage: Middle Toarcian (~181 million years ago)
• Location: Somerset, England, UK
• Formation: Beacon Limestone Formation or equivalent Toarcian marine deposits
• Order: Ammonitida
• Superfamily: Hildoceratoidea
• Family: Hildoceratidae
• Described By: Oppel, mid-19th century

Morphology Features:

Skirroceras leptogyrale is known for its elegantly compressed shell, sharply defined ribbing, and a narrow, often fastigate (angular) venter. The ribs are typically fine and regularly spaced, bifurcating along the flanks and continuing across the venter. This creates a detailed, sculptured look that makes the species visually striking and scientifically diagnostic.

This specimen displays all key features of the species, with well-preserved ribbing and whorl structure — a premium collector’s piece.

Depositional Environment:

The fossil was preserved in a low-energy, offshore marine environment, likely within fine-grained limestone or calcareous mudstones that accumulated during the Toarcian marine transgression. These conditions are characteristic of the Beacon Limestone Formation in the Ilminster-Somerset region.

Stratigraphic & Biozone Context:

Skirroceras leptogyrale is commonly associated with the Leptogyrale Subzone of the Bifrons Zone, an important ammonite biozone in the Middle Toarcian. It is frequently used in biostratigraphy for correlating marine Jurassic sediments across Europe.

Scientific Importance:

As a zonal fossil, Skirroceras leptogyrale is essential for detailed Jurassic stratigraphy. Its morphology is also of interest in evolutionary studies of the Hildoceratidae family, making this fossil suitable for collectors, educators, and researchers alike.

Authenticity Guarantee:

All of our fossils are 100% genuine specimens, professionally sourced and prepared. Each fossil includes a Certificate of Authenticity, documenting its species, age, and discovery location.

This Skirroceras leptogyrale ammonite is a striking and scientifically meaningful example from the Middle Jurassic of Somerset — ideal for display, study, or personal fossil collections.