Perspicaris dilatus (Robison & Richards, 1981)

Perspicaris is a fossil arthropod from the Cambrian period. It was 2–3 centimetres (0.8–1.2 in) long and bivalved. The valves, encasing the thorax, were joined together by a dorsal hinge.

It is difficult to establish the lifestyle of Perspicaris. Its large eyes and other parts would suggest a swimming animal, yet it lacks claws, which seems to suggest a bottom feeder.

Two species of Perspicaris are found in the famous Burgess Shale in British Columbia, Canada. 202 specimens of Perspicaris are known from the Greater Phyllopod bed, where they comprise 0.38% of the community.

Perspicaris has been identified as an arthropod that is a member of a clade close to the crown-group of Euarthropoda, which includes myriapods, chelicerates, insects and crustaceans.