Indirect interactions between a native and a supposedly non-native wasp species (Hymenoptera: Vespidae: Eumeninae: Anterhynchium)

Non-native species pose a threat to native organisms. When non-native and are closely related, the former can often competitively exclude latter. Many studies have focused on competitive exclusion of insect by eusocial hymenopterans, including ants, hornets, paper wasps bees. Although solitary been introduced in many regions, few investigated effects these insects their congeners. We interactions between belonging same genus (Hymenoptera: Vespidae: Eumeninae: Anterhynchium). Specifically, we compared resource use natural enemies Anterhynchium flavomarginatum supposedly A. gibbifrons at forest edge Takasago, Hyogo, Japan, June-October 2019, using trap nests (bamboo canes). Of 950 bamboo canes, 70 (7.4%) 50 (5.3%) were used as gibbifrons, respectively. produced two generations over period studied, whereas only one. began nesting weeks after flavomarginatum, overlapped that first flavomarginatum. Nest architecture inner diameter canes both similar, suggesting potential competition for resources. larvae 14 moths (Lepidoptera: Crambidae, Pyralidae, Tortricidae) food larval offspring, single species, Demobotys pervulgalis Crambidae). Prey exclusive each wasp indicating no this resource. Three parasitoid Macrosiagon nasutum (Coleoptera: Ripiphoridae), Amobia distorta (Diptera: Sarcophagidae) Megaselia sp. Phoridae), attacked species. The percentage parasitism was higher may indirectly affect via shared parasitoids.