Predominant accumulation of a 3-hydroxy-γ-decalactone in the male rectal gland complex of the Japanese orange fly, .

The Japanese orange fly, , infests various citrus crops. While male pheromone components accumulated in the rectal glands are well characterized for , but information regarding the chemical factors involved in the life cycles of remains scarce. Herein, several volatile chemicals including a γ-decalactone, (3,4)-3-hydroxy-4-decanolide [(3,4)-HD], were identified as major components, along with acetamide and spiroketals as minor components in the rectal gland complexes of male flies.

First report of Cheiloneurus exitiosus (Perkins, 1906) and Helegonatopus dimorphus (Hoffer, 1954) (Hymenoptera: Encyrtidae) from Japan, with remarks on their abundance in rice paddies.

Background: Encyrtid secondary parasitoids of Delphacidae have not been recorded in Japan. However, they may play an important role in the rice ecosystem because they can reduce the number of Dryinidae, the natural enemies of rice planthoppers.

New Information: We found two encyrtid species, Cheiloneurus exitiosus (Perkins, 1906) and Helegonatopus dimorphus (Hoffer, 1954), from rice paddies and the surrounding environment.