SPERM COMPETITION IN THE FEMALE DIACHASMI MORPHA-LONGICAUDATA (HYMENOPTERA, BRACONIDAE)

Sperm competition was studied in the parasitoid Diachasmimorpha longic audata (Ashmead) (Hymenoptera: Braconidae) with a genetically marked s tock. Females mated more than once. The spermatozoids partially mixed within the spermatheca of the female when the interval between two mat ings was <6 min. The second mating male sired a mean progeny proportio n (Pz) of 0.49. At the beginning of the oviposition period, the sperma tozoids of the second mating male were released; those of the first ma le were released at the end of the oviposition period. Apparently the time period between the first and second copulation influences P2 beca use copulations with an interval of 24 h resulted in P2 congruent-to 0 .75. Some observations on the mating behavior are also described.