Abstract
A burgundy‐red pigment acquired by the tissue lining the abdominal wall during development of the ovarian follicles is invariably present in gravid Culicoides. The pigment persists after oviposition and can be detected in unengorged females with undeveloped ovaries with the aid of a dissecting microscope. The presence or absence of the pigment provides a method for recognition of individual nulliparous and parous empty Culicoides without dissection. It may be applied to living as well as refrigerated or deep frozen material and specimens stored in alcohol or cleared in creosote and mounted in baisam. Using this method conspecific series have been sorted according to sex, the females graded as blood‐engorged, gravid, nulliparous empty or parous empty and the numbers counted, at the rate of more than 1000 flies/hr.