1. Laboratory of Insect Ecology, Graduate School of Environmental Science, Okayama University, Okayama 700-8530, Japan.
2. Department of Entomology and W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC 27695–7613, USA.
3. Laboratory of Insect Ecology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan.
4. Faculty of Agriculture, University of the Ryukyus, Okinawa 900-0213, Japan.