At half the magnification of PHIL# 9241, this 2006 scanning electron micrograph (SEM) depicted a dorsal view of the right flexed foreleg of a female body louse, Pediculus humanus var. corporis, in its entirty. What is visible includes the most distal segment, known as the 'pretarsus', followed by the more proximal 'tarsus', then the 'tibia', 'femur', and 'trochanter', and finally the most proximal segment, the 'coxa'. In the case of the louse, the leg segments are very stout, and end in claws, which it used to firmly grasp clothing, or a host's hair shafts. Note how the exoskeletal covering appears to possess an almost fabric-like appearance to the chitinous exoskeleton, which acts to add flexibility at the coxa-trochanteric joint.
CDC/ Joseph Strycharz, Ph.D.; Kyong Sup Yoon, Ph.D.; Frank Collins, Ph.D.
December 3, 2012