These organisms possess a lorica consisting of separate dorsal and ventral plates, which are not connected at the edges, resulting in a thin and less developed appearance. Their bodies exhibit a prismatic or spindle-like shape, while their two toes are usually slender and curved. The foot is rudimentary, lacking articulated joints. Their mastax is virgate, featuring rami and unci with very basic structures. Unlike certain other species, they do not have a retrocerebral sac.