Trilobite - Fossilised animal - Walliserops issimourensis / Ptychopariida

A very nice Walliserops issimourensis and Ptychopariida from Atchana, Morocco, with perfect details.
Walliserops is one of the rarest species of trilobites, and it is exceptional to find it in the same matrix with another trilobite.
These are extinct arthropods belonging to the trilobites. They lived in the Lower Devonian (about 400 million years ago). Their remains have been mainly found in North Africa.
Trilobites (meaning "three-lobed entities") are extinct marine arthropods that form the class Trilobita. One of the earliest groups of arthropods to appear in the fossil record, trilobites were among the most successful of all early animals, existing in oceans for almost 270 million years, with over 22,000 species having been described.