This is a fairly scarce type of Proetid trilobite (Tropidocoryphe) from Morocco. I believe based on the rock, preservation and species it came from the Timrhanrhart Formation near Foum Zguid, but not 100%. It's .7" long and bears small spines on each axial ring. A nice specimen of a hard to find species.
Trilobites were a very diverse group of extinct marine arthropods. They first appeared in the fossil record in the Early Cambrian (521 million years ago) and went extinct during the Permian mass extinction (250 million years ago). They were one of the most successful of the early animals on our planet with over 25k described species, filling nearly every evolutionary niche. Due in large part to a hard exoskeleton (shell), they left a excellent fossil record.