Sensilla on the antenna and ovipositor of the parasitic wasps Trichogrammagalloi Zucchi and T-pretiosum Riley (Hym., trichogrammatidae).

The understanding of the stimuli perceived by these parasitoids to accept a nd exploit a potential host may support the development of artificial hosts for their in vitro rearing. The most common structures involved in the hos t selection process in parasitoids are the antenna and the ovipositor. Sens illa present on these structures are involved in host recognition and accep tance, and the identification of which kind of stimulus (physical or chemic al) is perceived by the sensilla could provide data about the host characte ristics that elicit the parasitism behavior. The antenna and ovipositor of the wasps Trichogramma galloi and T. pretiosum were studied to identify the ir sensillar structure and their possible functions in the host selection p rocess, as a support to the development of an artificial host for the in vi tro rearing of these parasitoids. Seven sensilla and one setiform structure were present on the antenna of both parasitoid species, with a mixed, chem o-, or mechanoreception function. The ovipositor has four different sensill a and their role in the host evaluation is suggested. Microsc. Res. Tech. 4 5:313-324, 1999. (C) 1999 Wiley-Liss, Inc.