Perisphinctes is an extinct genus of ammonite cephalopod that lived in the lower Jurassic 163 million years ago. Age: Lower Jurassic. Genus: Ammonite. Location: Tulear, Madagascar. Ammonites are one of the most recognisable fossils around, this is due to their familiar spiral shape shell, reminiscent of what we know as a snail shell, though these creatures are not related to snails at all!
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