Taxonomy of the genus Periacma Meyrick (Lepidoptera: Autostichidae) from China, with a checklist of the world species Author Wang, Shuxia College of Life Sciences, Nankai University, Tianjin 300071, China. Author Xu, Zhixin 0000-0001-6851-8234 College of Life Sciences, Nankai University, Tianjin 300071, China. text Zootaxa 2024 2024-01-11 5399 2 101 129 http://dx.doi.org/10.11646/zootaxa.5399.2.1 journal article 10.11646/zootaxa.5399.2.1 1175-5326 10493947 EC9BEA58-70C4-4BA2-B7FA-094F49A911A1 Periacma largiloba Wang , sp. nov. ( Figs 7 , 23 ) Type material. CHINA , Yunnan : Holotype ♂ , Jingpozhai ( 24º71′N , 97º39′E ), Nabang Town , Yingjiang County , 231 m , 3.VIII.2013 , leg. SR Liu et al. , slide No. LiSR16109 . Paratype : 1♂ , same data as holotype, slide No. LiSR16110 . Diagnosis. The new species is similar to P. equivalvata Wang, Li & Liu, 2001 in male genitalia. It can be distinguished by the short digitate dorso-proximal process of the valva, the sacculus with two apical denticles, and the aedeagus with one distal process twice as long as the other process. In P. equivalvata , the dorso-proximal process of the valva is slenderly clavate, the sacculus lacks denticles at apex, and the aedeagus has two distal processes subequal in length and shape. Description. Adult ( Fig. 7 ). Wingspan 10.5 ‒ 11.0 mm. Head. Vertex and frons yellow, mottled with black scales. Labial palpus yellow, second segment black distally. Antenna yellow; scape black and flagellum anuulated with black on dorsal surface. Thorax. Mesonotum black, yellow at base; tegula yellow. Forewing orange yellow, with black scales; costal margin black at base; arched black speckle from near base of dorsum obliquely outward crossing fold, then along above fold to near end of fold; discal spot black, elongate; postmedial fascia black, extending from costal 1/2 to tornus, arched outward medially; apical fascia wide, narrowed along termen; fringe yellow, mixed with black along termen, grey around tornus. Hindwing and fringe grey. Legs yellow, except three distal tarsomeres of fore- and midlegs black; on dorsal surface, foreleg with some black scales on femur and tibia, midleg with a few black scales on distal half of femur, tibia black at base, tarsus black at middle of first tarsomere and at base of second tarsomere. Male genitalia ( Fig. 23 ). Uncus narrowed from base to basal 1/4, then uniform to basal 1/2, distal 1/2 expanded elliptically. Gnathos annular, with small spines anteriorly. Valva with costal part subparallel to before obtusely rounded apex; costa almost straight; dorso-proximal process short, thumb shaped; sacculus slightly longer than half length of costal part of valva, narrowed from base to basal 2/3, distal 1/3 sub-digitate, with two denticles at apex. Aedeagus about 3/5 length of costal part of valva, gradually widened from base to middle, distal half consisting of two large processes: one process longer, narrowed to apex, with dense spines, the other process narrowed basally, sharply widened apically, produced into one longer lobe bearing teeth distally, and one short sub-triangular lobe with a pointed tip. Female unknown. Distribution. China ( Yunnan ). Etymology. The specific epithet is derived from the Latin largus- and -lobus , referring to the two distal processes of the aedeagus.