Swarming and Mating Behavior of a Natural Population of Culicoides Variipennis (Diptera: Ceratopogonidae)1

Abstract
Swarms of Culicoides variipennis are described, which are similar to those of Culicoides nubeculosus . These swarms were confirmed as mating sites in which matings were seen every 10–15 s. Extensive mating occurred despite a female : male sex ratio in the swarm of only 1:167 (sampled by sweep net). Coupling took place at the periphery of the swarm. Pairs fell to the ground and remained in copula from 30 to 120 s. Increased time in copula significantly increased successful insemination. Among females arriving at the swarm, 99.0% were nulliparous. The size and shape of the sensory pit on the 3rd segment of the maxillary palp was not a useful character in classifying coupled females as either C. variipennis or C. occidentalis .