Wikipedia
Ptychoparia
Ptychoparia is a genus of ptychopariid trilobites, and is the type genus of the family Ptychopariidae, and the order Ptychopariida.
Fossils of the various species are found in Middle Cambrian-aged marine strata of Eurasia and North America, about 513 ± 0.3 to 499 ± 1.7 million years ago.