A survey of specimens and the literature was conducted to determine the presence, distribution and possible phylogenetic significance of mesopostnotal setae and/or scales on adults throughout the family Culicidae. The distribution in the family is tabulated with detailed notes for the species in each taxon having the character, and 4 species with the character are illustrated. The presence and frequency of the character in various taxa of the tribes Aedini, Culicini and Sabethini are discussed highlighting differences in given taxa between the Eastern and Western Hemispheres. Phylogenetic considerations regarding the correlation of the character with the subtropics/tropics, phytotelmic immature habitats, and the origin of the current distribution of the character are discussed.
