Genus Mesoleptus Gravenhorst, 1829

Mesoleptus Gravenhorst, 1829: 3 . Type: Ichneumon laevigatus Gravenhorst, 1820 . Designated by Curtis (1837).

Exolytus Holmgren, 1859: 328 . Type: Ichneumon laevigatus Gravenhorst, 1820 . Monobasic.

Two species, Mes. laticinctus (Walker, 1874) and Mes. sapporensis (Uchida, 1930), have been recorded from Japan. I recognize a newly recorded species, Mes. laevigatus (Gravenhorst, 1829), and at least three undetermined species from Japan. The taxonomic treatment of the undetermined species requires the additional specimens and comparison with European species. In this study, I record Mes. laevigatus from Japan for the first time and some distribution records of Mes. sapporensis below.