THE LARVAL INSTARS OF APHIDIUS SMITHI (HYMENOPTERA: APHIDIIDAE)

Abstract
The pea aphid parasite Aphidius smithi Sharma & Subba Rao has four larval instars. The first and the fourth instars are mandibulate. The second instar possesses oral lobes but not mandibles. A bilobed feeding structure on the ventral side of the head of the third instar could function as a pharyngeal pump. The chief diagnostic features of each instar are illustrated with scanning electron micrographs. Variability in the number of larval instars among species of Aphidiidae is discussed.