Rare Fossil Ammonite Macrocephalites lophopleurus Jurassic Callovian Tulear Madagascar | Authentic Fossil

Description

This listing features a rare and scientifically important fossil of Macrocephalites (Pleurocephalites) lophopleurus, an ammonite species from the Lower Callovian stage of the Jurassic period. The specimen originates from the world-famous fossil beds near Tulear, Madagascar, renowned for their exceptional preservation of Jurassic marine fossils.

Geological Context:

• Fossil Type: Ammonite (Extinct marine cephalopod, related to squid and cuttlefish)
• Species: Macrocephalites (Pleurocephalites) lophopleurus (Spath, 1928)
• Order: Ammonitida
• Superfamily: Stephanoceratoidea
• Family: Macrocephalitidae
• Geological Stage: Lower Callovian (c. 166.1 to 164.7 million years ago)
• Formation: Marine limestones of Tulear Basin, southwestern Madagascar
• Depositional Environment: Shallow marine carbonate platform with rich benthic diversity

The genus Macrocephalites is known for its large, robust shells and significant role in Middle Jurassic biostratigraphy. The subspecies Pleurocephalites lophopleurus is especially rare, and valued for its distinct ribbing and pronounced morphological features.

Morphology & Notable Features:

• Strongly involute shell with broad, compressed whorls
• Dense, sinuous ribs that may bifurcate or trifurcate mid-flank
• Rounded to subangular venter, typically lacking keel
• Prominent suture lines characteristic of Macrocephalitid ammonites
• A rare and desirable subspecies with excellent display potential

Biozone Association: This species is associated with early Callovian biozones, particularly the Macrocephalites herveyi or Macrocephalites gracilis zones, which are critical for regional stratigraphic correlation in Madagascar and other parts of Gondwana.

Specimen Details:

• Origin: Tulear Region, Madagascar
• Age: Lower Callovian Stage, Jurassic (~165 million years old)
• Scale: Scale rule square/cube = 1cm. Please refer to the photo for full sizing
• Condition: Selected for excellent preservation, detail, and completeness
• Photo: You will receive the exact specimen shown in the photographs

Certification & Authenticity: All of our fossils are 100% genuine and come with a Certificate of Authenticity. Each specimen is hand-picked for scientific, educational, and collector value.

This rare Macrocephalites (Pleurocephalites) lophopleurus ammonite is a remarkable example of Jurassic marine life and an ideal addition to any serious fossil collection, educational display, or natural history showcase.