Sensilla on the antenna and ovipositor of the parasitic wasps trichogramma galloi Zucchi and T. pretiosum Riley (Hym., Trichogrammatidae).

The understanding of the stimuli perceived by these parasitoids to accept and exploit a potential host may support the development of artificial hosts for their in vitro rearing. The most common structures involved in the host selection process in parasitoids are the antenna and the ovipositor. Sensilla present on these structures are involved in host recognition and acceptance, and the identification of which kind of stimulus (physical or chemical) is perceived by the sensilla could provide data about the host characteristics that elicit the parasitism behavior. The antenna and ovipositor of the wasps Trichogramma galloi and T. pretiosum were studied to identify their sensillar structure and their possible functions in the host selection process, as a support to the development of an artificial host for the in vitro rearing of these parasitoids. Seven sensilla and one setiform structure were present on the antenna of both parasitoid species, with a mixed, chemo-, or mechanoreception function. The ovipositor has four different sensilla and their role in the host evaluation is suggested.