Specimens of the New World genus Leschenaultia Robineau-Desvoidy (Diptera: Tachinidae) parasitise a wide range of lepidopteran hosts, including economically important pests. The female flies are attracted to volatile compounds released by host plants in response to the herbivory of caterpillars. They deposit microtype eggs on the leaves, which are then ingested by the hosts. We record a new host for L. bicolor (Macquart), obtained from Halysidota pearsoni Watson (Lepidoptera: Erebidae) in Ouro Preto, Minas Gerais, Brazil. The record is described herein and a comparative diagnosis for the identification of this parasitoid is provided, with discussion on similar species of the genus. The male and female terminalia of L. bicolor are fully described and illustrated for the first time. We also review and update the host records for Leschenaultia in an annotated host catalogue. At least nine species of Leschenaultia are recorded from 53 species of Lepidoptera, including the families Apatelodidae, Erebidae, Lasiocampidae, Noctuidae, Nymphalidae, Saturniidae, and Sphingidae. Finally, we provide an overview of host use and host associations.

新世界属Leschenaultia Robineau-Desvoidy（Diptera：Tachinidae）的标本寄生多种鳞翅目寄主，包括具有重要经济意义的害虫。雌蝇被寄主植物响应毛毛虫的草食而释放的挥发性化合物所吸引。它们在叶片上沉积微型卵，然后由宿主吸收。我们记录了来自巴西米纳斯吉拉斯州欧鲁普雷图的Halysidota pearsoni Watson（鳞翅目：Erebidae）的双色乳杆菌（Macquart）的新宿主。本文描述了记录，并提供了鉴定该寄生虫的比较诊断，并讨论了该属的相似物种。双色乳杆菌的雄性和雌性终端首次完整描述和说明。我们还会在带注释的主机目录中查看和更新Leschenaultia的主机记录。至少有九个品种的Leschenaultia从53种鳞翅目，包括家庭Apatelodidae，Erebidae，枯叶，夜蛾科，蛱蝶科，大蚕蛾，和天蛾记录。最后，我们提供了主机使用和主机关联的概述。