2025-12-24 九州大学
図1.アラカワアリヤドリバチ雌間の空中での闘争行動
A:2個体の雌がモリシタクサアリの巣前でホバリング(黄・赤矢印)
B–C:巣前に位置していた雌(赤矢印)が、接近してきた雌(黄矢印)に体当たりし、突き飛ばす様子
D:突き飛ばされた雌(黄矢印)がアリの巣に運び込まれる様子
<関連情報>
- https://www.kyushu-u.ac.jp/ja/notices/view/3023
- https://link.springer.com/article/10.1007/s00040-025-01072-8
Ogkosoma cremieri(膜翅目:ヒメバチ科:ヒブリゾンチ亜科)のLasius capitatus(膜翅目:アリ科)に対する寄生戦略 Parasitoidic strategy of Ogkosoma cremieri (Hymenoptera: Ichneumonidae: Hybrizontinae) against Lasius capitatus (Hymenoptera: Formicidae)
S. Kajiwara & T. Yamauchi
Insectes Sociaux Published:13 December 2025
DOI:https://doi.org/10.1007/s00040-025-01072-8
Abstract
From late September to mid-October 2022 in Hokkaido, Japan, females of Ogkosoma cremieri (Romand) (Ichneumonidae: Hybrizontinae) were observed hovering near the nest entrance of Lasius capitatus (Kuznetsov-Ugamsky) (Formicidae), approaching larvae carried by worker ants. Females sometimes aggressively pushed each other in competition over hosts. Individuals that were knocked away were occasionally attacked by ants and carried into the nest. These observations suggest intraspecific competition among females over limited host resources and a high risk of ant attack during oviposition attempts. Nighttime observations revealed active larval transport by ants, but no parasitoidic behavior by O. cremieri, suggesting that females are inactive at night. Parasitoidism of social insects faces high barriers due to their collective defenses and complex communication systems, making understanding parasitoid adaptations essential for elucidating host–parasitoid interactions. Our findings provide insight into the behavioral evolution of parasitoid wasps and the evolutionary arms race between hosts and parasitoids.
