(Fig. 97, 151, 236, 272)

Culicoides posoensis Wirth and Blanton, 1969a: 562 (female, male; fig. female antenna, palpus, wing, eye separation, spermathecae, male genitalia, parameres; California). Wirth et al. 1985: 38 (numerical characters; fig. female wing).

Diagnosis. (Tables 14, 15) Brown; wing pattern reduced, with pale spots only on wing base, at tip of costa, on r-m crossvein; tibiae with faint basal pale band; two subequal ovoid spermathecae with fingerlike vestigial third; sclerotized ring on spermathecal duct; ventro-posterior membrane of male sternite 9 bare; gonocoxal apodemes simple, ventral apodeme thin,>5× longer than wide; aedeagus Y-shaped, basal arms curved, median process simple with truncate tip ~0.2 as wide as basal arch, aedeagal ratio ~0.5; parameres separate, apical half simple thin sinuous.

Distribution. California (Kern County).

Adult behavior. Using truck traps in Kern County, California, Nelson and Bellamy (1971) found C. posoensis was more abundant in the summer than in the fall, with flight activity through the night with peaks near dusk and dawn. However, little else is known about the biology of this species other than that the mandibular and lacinial teeth on the female indicate it feeds on vertebrate blood.