Trilobites thrived throughout the Paleozoic world, comprising one of the earliest known groups of arthropods. They flourished to over 600 species at their zenith, including many with exotic exoskeletons and unique feeding strategies. They are probably most closely related to modern horseshoe crabs.
Though the Cambrian (521 mya) marks the appearance of trilobites in the fossil record, they were already highly diverse. They continued to proliferate until their decline in the Devonian and eventual disappearance in the Permian mass extinction (250 mya).
This Calymene Trilobite comes from Morocco, North West Africa and has had some repair work done as is common with these fossils.