RARE Paragarantiana alticostata Fossil Ammonite – Upper Bajocian, Jurassic, Eurecy Calvados France – Genuine + COA

Description

An exceptionally rare and scientifically significant Paragarantiana alticostata Fossil Ammonite, from the Upper Bajocian Stage of the Jurassic Period, collected near Eurecy, Calvados, Normandy, France. This ammonite features high, prominent ribbing and excellent preservation, making it a valuable specimen for collectors and biostratigraphers alike. The specimen shown in the photo is the exact one you will receive and comes with a Certificate of Authenticity.

Fossil Type & Species:

• Type: Ammonite (extinct marine cephalopod)
• Species: Paragarantiana alticostata
• Order: Ammonitida
• Superfamily: Stephanoceratoidea
• Family: Stephanoceratidae

Geological Context:

• Period: Jurassic
• Epoch/Stage: Middle Jurassic – Upper Bajocian (approx. 170.3 to 168.3 million years ago)
• Biozone: Likely from the Garantiana or Parkinsonia zone, common to ammonite-bearing strata in NW Europe
• Depositional Environment: Marine shelf, within alternating marl-limestone beds, providing excellent fossil preservation conditions

Locality:

• Region: Eurecy, Calvados, Normandy, France
• Formation: Bajocian sedimentary sequence of the Paris Basin (precise unit not confirmed)

Morphology & Features:

• Evolute shell with broad umbilicus
• Extremely high, sharply defined ribs that give the species its name “alticostata” (high-ribbed)
• Strong bifurcation of ribs low on the flank
• Ribs continue uninterrupted across the venter

Scientific Notes:

• Paragarantiana alticostata is a zonally important species described during the refinement of Bajocian ammonite taxonomy in the 20th century
• This genus is relatively rare and well-preserved examples are prized in biostratigraphic and museum collections

Notable Details:

• Exceptional preservation; natural and unrestored
• Scientifically informative and visually striking specimen
• Scale Reference: Each square or cube = 1cm. See the image for exact fossil dimensions

Authenticity & Guarantee: All of our fossils are 100% genuine, professionally curated and responsibly sourced. A Certificate of Authenticity is provided with each item. You will receive the exact fossil shown.

This rare Paragarantiana alticostata ammonite is an outstanding piece for collectors, academic study, or display. A classic fossil from the richly fossiliferous marine strata of Jurassic Normandy.