(Based on drawing in Walter and Shaw 2004)
The parasitic form of Leptotrombidium is the larva, which is easily identified by the possession of just three pairs of legs, instead of the four pairs possessed by the free-living nymph and adult stages. The body and legs are covered with numerous setae, and the cuticle may appear wrinkled. The mouthparts have the characteristic central pair of chelicerae surrounded by a pair of palps.