Peritrophic membrane formation and the midgut barrier to arboviral infection in the mosquito, Culex tarsalis Coquillett (Insecta, Diptera).

The formation of the peritrophic membrane in adult female mosquitoes, Culex tarsalis, was examined by light and electron microscopy. The initial evidence of secretion of peritrophic membrane precursors occurred at 8-12 h after ingestion of the bloodmeal. Morphogenesis of the peritrophic membrane occurred within 12-16 h after the initial secretion; culminating with a fibrous, multilayered peritrophic membrane 20-24 h after bloodmeal ingestion. A discussion of the potential participation of the peritrophic membrane in a midgut barrier to infection by arboviruses is presented. The participation of the peritrophic membrane in a midgut barrier to infection of C. tarsalis, and many other mosquito species, by arboviruses is considered a moot point.