Periacma ludingensis 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 : 113-114

Periacma ludingensis Wang , sp. nov.

( Figs 11 , 26 , 41 )

Type material. CHINA, Sichuan: Holotype ♂, Hailuogou (29.36ºN, 102.6ºE), Luding, 1695 m, 1.VII.2016, leg. KJ Teng & XF Yang, slide No. XZX20613 . Paratypes: 1♂ 1♀, sama data as holotype, slide No. XZX20614 ♀ .

Diagnosis. The new species is similar to P. ziyangensis Wang & Zheng, 1995 . It can be distinguished by the sacculus with a tooth near the apex on the ventral margin, and the aedeagus without a long spine from the middle in the male genitalia; and the signum being a small triangular plate with a large spine in the female genitalia. In P. ziyangensis , the sacculus has a narrow plate placed before the apex, and the aedeagus has a long spine arising from the middle; and the signum is absent.

Description. Adult ( Fig. 11 ). Wingspan 16.0 ‒ 18.0 mm.

Head. Vertex and frons pale yellow, mixed with light brown scales. Labial palpus yellow; in male, second segment with black scales on ventral surface, ringed with black near apex; in female, second segment with dense brown scales distally, third segment with dense black scales on ventral surface. Antenna with scape yellow on ventral surface, black on dorsal surface; flagellum yellow, annulated with dark brown on dorsal surface.

Thorax. Mesonotum dark brown, with yellow scales laterally; tegula yellow, with dark brown scales. Forewing yellow; costal margin dark brown at base; dorsum with a large dark brown speckle at base, extending obliquely outward to fold, then along fold to distal 1/4 above fold; discal spot dark brown, parallel with postmedial fascia; postmedial fascia dark brown, from about costal 3/5 to tornus; apical patch dark brown, diffused; fringe yellow. Hindwing and fringe grey. Legs yellow, except three distal tarsomeres of foreleg deep brown; on dorsal surface, foreleg with yellowish brown scales on femur and tibia, tarsus deep brown at middle of first tarsomere, midleg with some brown scales on tarsus; on outer surface, hindleg blackish brown at middle of first tarsomere and at base of other tarsomeres.

Male genitalia ( Fig. 26 ). Uncus gradually widened to apex, apex obtusely rounded and with two teeth. Gnathos with ventral plate narrow and subparallel posteriorly, sharply widened anteriorly, horizontally narrowed outward to pointed end anterolaterally. Valva with costal part narrowed from base to basal 2/5, then elliptically widened to before narrowly rounded apex; costa distinctly concave before middle; dorso-proximal process dilated distally, setose; sacculus longer than 1/2 length of costal part of valva, wide at base, narrowed to basal 3/5, distal 2/5 suddenly produced to a narrow process bent dorsad, with a denticle near apex on ventral margin. Saccus short and broad, sub-trapezoidal. Aedeagus slightly widened to basal 2/3, distal 1/4 produced to a sub-quadrate plate with denticles apically.

Female genitalia ( Fig. 41 ). Papilla anale sub-triangular. Apophysis posterioris longer than 2 times length of apophysis anterioris. Eighth sternal plate spinulate, concave at middle and with long setae on posterior margin. Antrum wider than ductus bursae. Ductus bursae tubular, membranous. Corpus bursae sub-elliptical; signum being a small triangular plate with a curved spine.

Distribution. China (Sichuan).

Etymology. The specific epithet is from the type locality, Luding County, Sichuan Province.

Figures

FIGURES 10‒18. Adults of Periacma spp. 10. P. platygnatha sp. nov., holotype; 11. P. ludingensis sp. nov., holotype; 12. P. mediacantha sp. nov., holotype; 13. P. nakhonnayokensis; 14. P. nepalensis; 15. P. rectignatha; 16. P. securiformis sp. nov., holotype; 17. P. solitaridens sp. nov., holotype; 18. P. subaequalis sp. nov., holotype. Scales = 2.0 mm.

FIGURES 25‒28. Male genitalia of Periacma spp. 25. P.platygnatha sp. nov., holotype, slide No.LiSR16014; 26. P. ludingensis sp. nov., holotype, slide No. XZX20613; 27. P. mediacantha sp. nov., holotype, slide No. ZXJ18476; 28. P. nakhonnayokensis, slide No. ZXJ18211. Scales = 0.2 mm.

FIGURES 39‒44. Female genitalia of Periacma spp. 39. P. lianzhouensis, comb. nov., slide No. HS14110; 40. P. platygnatha sp. nov., paratype, slide No. XZX20689; 41. P. ludingensis sp. nov., paratype, slide No. XZX20614; 42. P. nepalensis, slide No. XZX20770; 43. P. Rectignatha, slide No. ZXJ18064; 44. P. subaequalis sp. nov., paratype, slide No. XZX20625. Scales = 0.5 mm.