Rare Pseudomercaticeras rotarium Ammonite Fossil, Lower Toarcian Stage Jurassic, Authentic Italian Collectors Specimen with COA

Description

Authentic Jurassic Ammonite Fossil

This listing offers a genuine Pseudomercaticeras rotarium Ammonite Fossil from the Lower Toarcian Stage of the Early Jurassic period, found in Italy. Ammonites were extinct marine cephalopods belonging to the subclass Ammonoidea and order Ammonitida. Their beautifully coiled shells are some of the most recognisable fossils worldwide, valued for both their scientific importance and their aesthetic beauty. This carefully chosen specimen highlights the distinctive features of Pseudomercaticeras rotarium. The photographs show the exact ammonite you will receive, with a 1 cm scale cube included for precise measurement.

Geological Context – Lower Toarcian, Jurassic

The fossil comes from the Lower Toarcian, dating to approximately 182 million years ago, a time of profound evolutionary and environmental change. The marine sediments of Italy from this interval were deposited in shallow seas, rich with ammonites and other invertebrates. These conditions allowed for excellent fossilisation, preserving ammonites in fine detail.

The Lower Toarcian is a vital period in paleontology, closely associated with the Early Toarcian Oceanic Anoxic Event. This event reshaped marine ecosystems, leaving behind a highly distinctive fossil record. Ammonites from this interval are particularly important as index fossils, helping geologists to establish precise biozones and to correlate rock layers across Europe and beyond.

Species Profile – Pseudomercaticeras rotarium

The ammonite Pseudomercaticeras rotarium belongs to the family Hildoceratidae, within the superfamily Hildoceratoidea. This family is known for compressed shells, pronounced ribbing, and evolute coiling. Pseudomercaticeras is an important genus for Toarcian stratigraphy, providing valuable markers within ammonite zonation schemes.

Key identifying traits of Pseudomercaticeras rotarium include:

• Evolute shell form with open umbilicus, allowing visibility of inner whorls.
• Fine, regular ribbing radiating from the umbilical edge across the flanks.
• A compressed whorl section with elegant coiling.
• Distinctive suture patterns marking the internal chamber divisions.

These features make Pseudomercaticeras rotarium both scientifically valuable and visually appealing as a display fossil.

Paleoenvironment and Scientific Value

During the Early Jurassic, the region that is now Italy was submerged under warm, shallow seas. Ammonites such as Pseudomercaticeras rotarium thrived as nektonic predators, moving actively through the water column and feeding on smaller marine animals. After death, their shells settled to the seafloor and were buried by fine sediments, resulting in their preservation for nearly 182 million years.

Because of their restricted stratigraphic ranges, ammonites like Pseudomercaticeras rotarium are invaluable in defining Lower Toarcian ammonite biozones. They are used by geologists and paleontologists to correlate rock strata across wide geographic regions. For collectors, this means owning a specimen that not only holds aesthetic appeal but also represents an important scientific tool in understanding Earth’s geological past.

100% Genuine with Certificate of Authenticity

All of our fossils are guaranteed 100% genuine specimens and come with a Certificate of Authenticity. This ammonite is not a cast or reproduction but an authentic relic of the Jurassic seas of Italy, preserved for millions of years.

Perfect for Collectors and Enthusiasts

This Pseudomercaticeras rotarium ammonite fossil from Italy is an excellent addition to any fossil collection or educational display. Its combination of geological significance, scientific value, and natural beauty makes it a specimen of lasting interest to collectors, paleontologists, and enthusiasts of natural history alike.

Scale Rule Squares / Cube = 1 cm. Please see listing photos for the full sizing of this actual specimen.