Ptychopariina is an extinct suborder of trilobites of the order Ptychopariida.[1] Also known as the primitive Ptychopariida, they are a notably wide and varied taxon.[2] Some of the representative genera include Elrathia, Densonella, Norwoodia, Tricrepicephalus, Conocoryphe, and Modocia.[2]
Specialization is common in the Ptychopariina, which has made it difficult for authors to develop a single type that can distinguish Ptychopariina from other clades. The thorax tends to be relatively long, with the pygidium generally smaller in size than the thorax.[2]