This was one of five scanning electron micrographic (SEM) images (PHIL# 9243 - 9247), successively magnified at higher and higher values, which focused on the head region of a female body louse, Pediculus humanus var. corporis from a ventral perspective. At a relatively low magnification, this SEM revealed some of the insect's exoskeletal morphology exhibited by its cephalic, or head region, thoracic, and proximal abdominal regions. Of interest is the jointed configuration of its six extremities, from which it derived its classification in the phylum of Athropoda, i.e., Arthro from "joint', and poda from "leg"). Also note the sensorial 'hairs' known as 'setae, which really aren't hairs at all, but chitinous exoskeletal extensions, unlike mammalian hairs, which are made up of keratin, and make mammals unique in this regard.
CDC/ Joseph Strycharz, Ph.D.; Kyong Sup Yoon, Ph.D.; Frank Collins, Ph.D.
December 3, 2012