Wiwaxia is a genus of soft-bodied, scale-covered animals known from Burgess shale type Lagerstätte dating from the upper Lower Cambrian to Middle Cambrian. The organisms are mainly known from dispersed sclerites; articulated specimens, where found, range from 3.4 millimetres (0.13 in) to a little over 50.8 millimeters (2 in) in length. They bear a set of mouthparts comprising two to three identical rows of rasping teeth that lay on a supporting apparatus or "tongue"; this feeding arrangement seems to represent a 'prototype' molluscan radula.
Read more about Wiwaxia: History of Discovery, Occurrence, Description, Ontogeny, Classification