Immature stages of Utetes anastrephae (Hymenoptera: Braconidae) developed in Anastrepha fruit fly larvae (Diptera: Tephritidae).

The morphology of the immature stages of Utetes anastrephae (Hymenoptera: Braconidae), a native parasitoid of larvae of flies of the Neotropical genus Anastrepha (Diptera: Tephritidae), is shown. This study aimed to characterize the immature stages and morphological changes in the development of the koinobiont endoparasitoid in two species of larval hosts, Anastrepha obliqua and Anastrepha ludens. The definition of structures and morphological changes during development was made through daily microscopic observations and photographs of dissected hosts. The immature development of the parasitoid corresponds to a holometabolous insect with three well-defined stages: egg (two days), larva with three larval instars (approximately eight days), and pupa (six days). Similar development times were obtained in the two host species. Males and females completed their cycle in 17 and 18 days, respectively. During egg-first instar development, host antagonistic activity through melanization and encapsulation as mortality factors was evident and frequent only in A. obliqua. These results serve as basic knowledge for the use of this parasitoid in the biological control of fruit flies.