Inchworm

A caterpillar of a Geometridae species of moth which lack the prolegs of other Lepidopteran caterpillars in the middle portion of the body, with only two or three pairs at each end. Equipped with appendages at both ends of the body, a caterpillar will clasp with its front legs and draw up the hind end, then clasp with the hind end (prolegs) and reach out for a new front attachment - creating the impression that it is measuring its journey. The caterpillars are accordingly called loopers, spanworms, or inchworms after their characteristic looping gait.