Kleptoparasitism as an explanation for paradoxical oviposition decisions of the parasitoid Asobara tabida

It is known that the braconid Asobara tabida, a parasitoid of Drosophila la rvae, takes oviposition decisions in accordance with survival probabilities in several host species. Nevertheless, larvae of D, simulans, in which the survival probability is virtually zero, are readily accepted for ovipositi on by searching females. This even happens when they are offered together w ith D. melanogaster larvae, in which the parasitoid can develop. Here I sho w that A. tabida can act as a kleptoparasitoid in D. simulans larvae: it ca n develop in D. simulans larvae, once these larvae are parasitized by anoth er parasitoid, the eucoilid Leptopilina boulardi. Analysis with an optimal foraging model suggests that the increase in survival probability and the o ccurrence of L, boulardi in the field are high enough to make this kleptopa rasitic behaviour of A. tabida pay.