Naraoidia

Naraoidia are soft shelled trilobites that are known only from the Early and Middle Cambrian -- primarily from the Burgess Shale of British Columbia and the Maotianshan Shale of China. There is a single genus -- Naraoia naraoia is considered to be a trilobite but has two peculiar features. The body covering is entirely unmineralized, and there is no thorax. Maximum size is about 4cm. A second softbodied trilobite -- Tegopelte -- is known from the same formations, but it may be only distantly related to Naraoia.