Large Jurassic Perisphinctes ammonite with other fossils embedded in it. Madagascar, Jurassic

Large Jurassic Perisphinctes ammonite with encrustations of other fossils. Madagascar, Jurassic, ca. 165–150 million years.
Condition: Good overall condition, with wear, concretions, and natural fractures typical of the fossilization process.
Measurements: 51 cm tall; 12.5 cm at its widest point.

An impressive fossil specimen of an ammonite belonging to the genus Perisphinctes, from the famous Jurassic sites of Madagascar, renowned for the quality and abundance of their marine fossils. The specimen stands out for its large size, the definition of its spiral structure, and the presence of natural incrustations of other Jurassic fossils embedded in the original matrix.

Ammonites were marine cephalopod mollusks that inhabited prehistoric oceans for much of the Mesozoic Era. Their characteristic spiral-coiled shell, divided internally into chambers, is one of the most recognizable and prized fossil forms, both for its scientific value and its great aesthetic appeal. The genus Perisphinctes, particularly representative of the Jurassic, is distinguished by its evolute, open-spiral shell and by its pronounced radial ornamentation.

Formed approximately 165 to 150 million years ago, this specimen is an extraordinary testament to the ancient Jurassic marine ecosystems. Its size allows one to clearly appreciate the shell’s elegant spiral morphology, as well as the regular ribs that run across the surface from the central core toward the outer perimeter. This natural structure, preserved over millions of years, gives the piece a powerful sculptural presence.

The surface features natural incrustations of other Jurassic fossils, a particularly attractive feature that adds paleontological richness and uniqueness to the piece as a whole. These inclusions, preserved alongside the main ammonite, evoke the sedimentary context in which the organism was deposited and fossilized, reinforcing the piece’s scientific and visual interest.