Taxonomy of Homoeusa Kraatz, 1856 (Coleoptera, Staphylinidae, Aleocharinae) from the East Palearctic: II. Revision of Japanese species

Members of the myrmecophilous rove beetle genus Homoeusa Kraatz, 1856 are symbiotically associated with ants of the genus Lasius Fabricius, 1804 with a high degree of host specificity, making them biologically intriguing subjects for studying myrmecophily and host – parasite interactions. Their identification, however, remains challenging. Diagnostic characteristics, particularly the genitalia, have not been well documented for the three previously described species of the genus from Japan, and the presence of undescribed species has been suggested.

In this study, we revise the taxonomy of Japanese Homoeusa, providing detailed descriptions and illustrations of seven species, including three new species: Homoeusa translucida sp. nov., Homoeusa brevitarsis sp. nov., and Homoeusa gigantea sp. nov. Additionally, we present ecological information for each species and discuss their interactions with their host ants.