Periacma anterosinuata Wang, 2024

Wang, Shuxia & Xu, Zhixin, 2024, Taxonomy of the genus Periacma Meyrick (Lepidoptera: Autostichidae) from China, with a checklist of the world species, Zootaxa 5399 (2), pp. 101-129 : 103

Periacma anterosinuata Wang , sp. nov.

( Figs 2 , 19 , 34 )

Type material. CHINA, Sichuan: Holotype ♂, Bifengxia (30.4ºN, 102.58ºE), Ya’an, 1115 m, 28.VI.2016, leg. KJ Teng & XF Yang, slide No. XZX20611 . Paratypes: 2♂ 1♀, same data as holotype except dated 27‒28.VI.2016, slide Nos. XZX20865♂, XZX20867♂, XZX20612 ♀ .

Diagnosis. The new species is similar to P. novella Wang, Li et Liu 2001 . It can be distinguished in the male genitalia by the apically obtuse uncus without teeth at middle on the posterior margin, and the costa of the valva without a process. In P. novella , the apically produced uncus has two small teeth at middle on the posterior margin, and the costa of the valva has a small toothlike process at basal 1/5.

Description. Adult ( Fig. 2 ). Wingspan 16.0 ‒ 16.5 mm.

Head. Vertex and frons yellow. Labial palpus yellow; in male, first segment black on dorsal surface, second segment with distal 1/2 black on ventral surface; in female, second segment with black scales in distal 1/2 on outer surface. Antenna with scape black on dorsal surface, yellow on ventral surface; flagellum yellow, alternated with black on dorsal surface.

Thorax. Mesonotum dark brown, mixed with yellow scales; tegula yellow, mixed with dark brown scales. Forewing orange yellow, with scattered dark brown scales; costal margin black from base to basal 1/5; dorsum with a dark brown spot at base; large speckle from base of dorsum extending outward to fold, then along fold to before middle length of wing; discal spot black, placed above preceding speckle; postmedial fascia dark brown, extending from about costal 2/3 to tornus; apical fascia dark brown, running along termen to postmedial fascia; fringe grey. Hindwing and fringe grey. Legs yellow, except four distal tarsomeres of foreleg black; on dorsal surface, foreleg with first tarsomere black at middle, midleg with tibia black at base, tarsus black at middle of first tarsomere and at base of other tarsomeres; on outer surface, tibia of hindleg with black scales.

Male genitalia ( Fig. 19 ). Uncus narrow and parallel sided from base to before middle, then gradually widened to before obtusely rounded apex, with long setae near base laterally. Gnathos with basal arm widened, shorter than ventral plate; ventral plate narrow and parallel sided posteriorly, suddenly widened anteriorly, extending outward and narrowed to rounded end laterally, slightly sinuate on anterior margin. Valva with basal half of costal part narrow, subparallel, distal half slightly wider, rounded at apex; costa concave medially, slightly convex at basal 1/5 and 4/5; dorso-proximal process dilated distally, setose; sacculus 3/5 length of costal part of valva, bilobed apically: dorsal lobe longer, digitate; ventral lobe shorter, sub-triangular. Saccus semicircular. Aedeagus half length of costal part of valva, widened medially, with a belt-like plate beyond middle; distal 1/4 suddenly produced to a plate narrowed to rounded apex, with small auriculate process at distal 1/8 laterally.

Female genitalia ( Fig. 34 ). Papilla anale gradually narrowed, setose. Apophysis posterioris three times as long as apophysis anterioris. Eighth sternal plate concave medially and with long setae on posterior margin. Lamella antevaginallis produced laterally. Antrum smooth, sclerotized. Ductus bursae short, sclerotized, densely spinuled. Corpus bursae spherical; signum narrowly elongate, edged with teeth, placed at anterior end.

Distribution. China (Sichuan).

Etymology. The specific epithet is derived from the Latin antero- and sinuatus, referring to the weakly sinuate anterior margin of the gnathos.

Figures

FIGURES 1‒9. Adults of Periacma spp. 1. P. acriuncata; 2. P. anterosinuata sp. nov., holotype; 3. P. falcata sp. nov., holotype; 4. P. ferialis; 5. P. himalayensis; 6. P. kunai; 7. P. largiloba sp. nov., holotype; 8. P. laterispinulosa sp. nov., holotype; 9. P. lianzhouensis, comb. nov. Scales = 2.0 mm.

FIGURES 19–24. Male genitalia of Periacma spp. 19. P. anterosinuata sp. nov., slide No. XZX20611, holotype; 20. P. falcata sp. nov., holotype, slide No. XZX20831; 21. P. ferialis, slide No. LiSR16106; 22. P. himalayensis, slide No. XZX767; 23. P. largiloba sp. nov., holotype, slide No. LiSR16109; 24. P. laterispinulosa sp. nov., holotype, slide No. XZX20576. Scales = 0.2 mm.

FIGURES 33‒38. Female genitalia of Periacma spp. 33. P. acriuncata, slide No. XZX20717; 34. P. anterosinuata sp. nov., paratype, slide No. XZX20612; 35. P. ferialis, slide No. XZX20850; 36. P. himalayensis, slide No. XZX20768; 37. P. kunai, slide No. XZX20814; 38. P. laterispinulosa sp. nov., paratype, slide No. ZXJ18472. Scales = 0.5 mm.