Geographical distributions and host associations of larval parasitoids of frugivorous Drosophilidae in Japan

Abstract

In Japan, dominant parasitoids attacking frugivorous Drosophilidae species were Asobara (Braconidae, Alysiinae), Leptopilina, and Ganaspis species (Figitidae, Eucoilinae). Asobara japonica was found throughout Japan, and its populations in the main islands of Japan were parthenogenetic whereas those in the subtropical islands were sexually reproducing. Other parasitoids showed rather restricted distributions; A.tabida, A. rossica, A. rufescens, and Leptopilina heterotoma occurred mainly in northern to central parts of the main islands, Ganaspis xanthopoda from central to southern parts of the main islands, A. leveri in a southern part of the main islands, and A. pleuralis, L. victoriae, and Ganaspis sp. mainly in the subtropical islands. Their major hosts were species of the D. melanogaster species group in the main islands, and species of the D. melanogaster, immigrans, and polychaeta species groups in the subtropical islands. Host use considerably varied among parasitoid species, especially in the subtropical islands.

Keywords:

• Braconidae
• Drosophilidae
• Figitidae
• geographic distribution
• host association
• parasitism

Acknowledgements

We are grateful to Dr K. Kamijo for identification of Pachycrepoideus species, and A. Oikawa and M. Kondo for their help with the field studies. This work was supported by a Grant‐in‐Aid from the Ministry of Education, Science, Sports and Culture of Japan (No. 17570010).