ABSTRACT Parasitoid wasps of the subfamily Hyptiogastrinae (Gasteruptiidae) are known to lay eggs in the nests of solitary bees and wasps. Their larvae are considered predator-inquilines, consuming the host’s eggs and larvae and then the nest provisions. Pseudofoenus extraneus is endemic to Fiji, and the only member of the subfamily Hyptiogastrinae known to have colonised the archipelago. The host relationships and oviposition sequence of this species have not been previously reported. We show that the primary host is the halictine bee Homalictus fijiensis and describe P. extraneus behaviour around Homalictus nest aggregations and the entering of host nests. Wasps were observed entering Homalictus nests on nine occasions, as well as perching near nests and antennating nest entrances. The high abundance of H. fijiensis in Fiji may help to explain how a parasitoid was able to successfully invade such a remote oceanic archipelago as Fiji.

中文翻译：

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斐济捕食者-inquiline 黄蜂Pseudofoenus extraneus（膜翅目：Gasteruptiidae：Hyptiogastrinae）的生殖行为学

摘要 寄生蜂亚科 Hyptiogastrinae (Gasteruptiidae) 已知会在独居的蜜蜂和黄蜂的巢穴中产卵。它们的幼虫被认为是捕食者-inquilines，消耗宿主的卵和幼虫，然后是巢穴食物。Pseudofoenus extraneus 是斐济的特有种，是已知在该群岛定居的 Hyptiogastrinae 亚科的唯一成员。该物种的寄主关系和产卵序列以前没有报道过。我们表明主要宿主是 halictine 蜜蜂 Homalictus fijiensis，并描述了 Homalictus 巢聚集和宿主巢进入周围的 P. extraneus 行为。观察到黄蜂有 9 次进入 Homalictus 的巢穴，以及栖息在巢穴附近和触角的巢穴入口。高丰度的H.