A review of the subgenus Delineatia Volynkin & Huang, 2019 of the genus Ammatho Walker, 1855, with descriptions of two new species from Taiwan and Vietnam (Lepidoptera, Erebidae, Arctiinae, Lithosiini) Author Volynkin, Anton V. Altai State University, Lenina Avenue, 61, RF- 656049, Barnaul, Russia. & National Research Tomsk State University, Lenina Avenue, 36, RF- 634050, Tomsk, Russia Author Wu, Shipher Biodiversity Research Center, Academia Sinica, No. 128, Sec. 2, Academia Rd., Nangang Dist., Taipei City 11529, Taiwan. shipher @ gmail. com; https: // orcid. org / 0000 - 0003 - 2264 - 7238 text Zootaxa 2020 2020-06-18 4801 2 237 250 journal article 21639 10.11646/zootaxa.4801.2.2 a1540ced-2e09-452a-bd37-aee70242bf23 1175-5326 3900426 C8430970-E584-4B98-B515-38CD47ADA90E Subgenus Delineatia Volynkin & Huang, 2019 Ammatho ( Delineatia ) Volynkin & Huang in Volynkin, Huang & Ivanova, 2019 , Ecologica Montenegrina 26 : 21, figs 15, 16, 111, 167 ( Type species: Hypoprepia delineata Walker, 1854 , by the original designation). Diagnosis . Medium-sized moths with red colouration and blackish pattern. Externally, members of the subgenus are similar to species of the subgenus Conicornuta Volynkin, 2019 of the genus Ammatho . Male genitalia of the subgenus are characterised by the combination of the following features: (1) the densely serrulate anellus; (2) the small medial costal process at very long and narrow, lobe-like base (an autapomorphic feature); (3) the very large and heavily sclerotised distal costal process bearing several denticles or short prominences; (4) the very small distal membranous lobe of valva; (5) the strongly setose sacculus; (6) the narrow vesica with short diverticula bearing clusters of very small spine-like cornuti or granulation. Female genitalia structure is typical for the genus Ammatho and is characterised by (1) the presence of a well-developed postvaginal plate; (2) the cup-like or funnel-like antrum and the very short anterior membranous section of corpus bursae; (3) the weakly scobinated posterior section of corpus bursae; (4) the membranous anterior section of corpus bursae lacking signa. Distribution . The subgenus is distributed in Indochina, mainland China and the island of Taiwan .