Hymenoptera show a great variation in reproductive potential and nesting behavior, from thousands of eggs in sawflies to just a dozen in nest-provisioning wasps. Reduction in reproductive potential in evolutionary derived Hymenoptera is often facilitated by advanced behavioral mechanisms and nesting strategies. Here we describe a surprising nesting behavior that was previously unknown in the entire animal kingdom: the use of a vestibular cell filled with dead ants in a new spider wasp (Hymenoptera: Pompilidae) species collected with trap nests in South-East China. We scientifically describe the ‘Bone-house Wasp’ as Deuteragenia ossarium sp. nov., named after graveyard bone-houses or ossuaries. We show that D. ossarium nests are less vulnerable to natural enemies than nests of other sympatric trap-nesting wasps, suggesting an effective nest protection strategy, most likely by utilizing chemical cues emanating from the dead ants. 2013-10-18 09:45:43 UTC final SP09e Aboveground multi-trophic plant-insect interactions in a Chinese subtropical forest Michael Staab michael.staab@nature.uni-freiburg.de Alexandra-Maria Klein alexandra.klein@nature.uni-freiburg.de Chao_Dong ZHU, Prof. zhucd@ioz.ac.cn Staab, M., Ohl, M., Zhu, C. D., & Klein, A. M. (2014). A Unique Nest-Protection Strategy in a New Species of Spider Wasp. PloS one, 9(7), e101592. 2014-07-02 accepted