Possible function of cephalic outgrowth of sucking lice (Anoplura) parasitic on tree shrews (Tupaiidae)

Speculation is made upon the significance of cephalic outgrowths in Sathrax durus and Docophthirus acinetus, 2 species of sucking lice (Anoplura) normally parasitic on tree shrews (Tupaiidae). An infestation of S. durus on a small laboratory colony of Tupaia glis provided lice for study. While the cephalic interspine spacing on S. durus could feasibly allow these spines to interlock with host underfur hairs, use in directly gripping host epidermis seems a more plausible function. No host fur was definitely trapped between spines, but attached fragments of host epidermis were common. Although D. acinetus specimens were not available for study, the larger cephalic protuberances on this species suggest that interlocking with host hairs is a distinct possibility. The protection of flexible joints is considered an unlikely function of these outgrowths.