On the taxonomy of the genus Isochlora Staudinger with descriptions of two new species from Mongolia and Qinghai, China (Lepidoptera: Noctuidae: Noctuinae).

Two new species of the genus Isochlora Staudinger, 1882 are described: I. hreblayi Volynkin, Tth, Titov & Saldaitis, sp. n. (western Mongolia) and I. kozlovi Volynkin, Titov, Matov & Saldaitis, sp. n. (Qinghai Province, China). The type species of the genus-group names Chamyla Staudinger, 1900 and Grumia Alphraky, 1892 (I. arctomys Alphraky, 1897 and I. flora (Alphraky, 1892), respectively) are examined, and their synonymy with Isochlora is revised. The synonymy of Chamyla idia Staudinger, 1900 with Isochlora arctomys Alphraky, 1897 is revised as junior synonymies. Lectotypes are designated for Isochlora arctomys Alphraky, 1897, Chamyla idia Staudinger, 1900 and Grumia flora Alphraky, 1892. Isochlora intricans (Alphraky, 1882) is reported from Kazakhstan for the first time. Adults as well as male and female genitalia are illustrated.