[C] Social insects

[C-47] オセアニアに分布拡大したフタモンアシナガバチの生態的特性

◯Koji Tsuchida¹, Katsuhiko Sayama², Fuki Morooka³ (1. Gifu University, 2. FFPRI, 3. Ibaraki University)

The Asian paper wasp Polistes chinensis was established in New Zealand in 1979 and collected in Australia in 1999, suggesting that it is expanding its distribution. Invasive species change their ecological characteristics between their native and invaded areas. This report presents our analysis of samples from Australia and the Tohoku and Hokkaido regions of Japan. We conducted a population genetic analysis and measured genetic relatedness. Three main results were obtained: (1) Australian population structure was independent of that of New Zealand and Japan; (2) Japanese population structure was more regionally varied than that of New Zealand and Australia, with populations similar to those in the Kyushu region detected in Yamagata Prefecture and Hokkaido; and (3) intra-nest relatedness was significantly lower in New Zealand and Australia. These results suggest that the wasps invaded Australia directly from Japan, and they experienced bottlenecks associated with the invasion, and colonies allowed individuals from other nests by drift.