Nygmia wui Pan & Ouyang, 2025

Nygmia wui Pan & Ouyang , sp. nov.

Figs 1–6 View FIGURES 1-13 , 14–17 View FIGURES 14–21 , 22–23 View FIGURES 22–26 .

Type material. Holotype ( Figs 1 View FIGURES 1-13 , 14 View FIGURES 14–21 ): male, “STS-88896, Beibeng Township , Motuo County, Linzhi City, Xizang, China, N: 29°24.351′, E: 95°16.974′, 12-Ⅴ-2017, h [Altitude] 781 m (coll. Pan Zhaohui)” gen. prep. No. STS-88896 ( XAAHU).

Paratypes: 1 male, Sejila Mountain , Linzhi City, Xizang, China, N:29°59′19′′, E: 95°01′02′′, 7-IX-2020 , h [ Altitude ] 2060 m (coll. Pan Zhaohui) ; 1 male, same data as holotype, but 9-VI-2017 ; 1 male, same data as holotype, but 17-15- Ⅴ -2023 ; 1 female, same data as holotype, but 16-VI-2017 ; 1 female, 80K, Damu Township , Motuo County, Linzhi City, Xizang, China, N: 29°39′4.5′′, E: 94°42′51.5′′, 25-VII-2015 , h [ Altitude ] 3932 m (coll. Pan Zhaohui), unique numbers: STS-73699, STS-50770, STS-79172, STS-72748, STS-55329, gen. preps .

Diagnosis: The new species can be separated from other congeners by the dark brown forewing with six irregular white spots on the external margin of the forewings. In male genitalia, the new species is distinguished by the tripartite sclerotized distal valvae structure. Nygmia wui sp. nov. resembles N. inornata (Wileman, 1910) externally, with nearly identical forewings and hindwings patterns, and the male genitalia share the following characteristics: Uncus digitiform and sclerotized; Valvae bifurcate, with sclerotized branches; Phallus constricted medially, broader at both base and apex; Vesica bearing a recurved, sclerotized spine basally ( Wang 2010). But differs in the male genitalia: i) valvae distally trifurcated with dorsal branch markedly stouter, middle branch slender with its tip bent outward, ventral branch shorter and triangular or spiniform, while in N. inornata , the distal end of the valvae is four-branched, with one branch from the ventral margin further splitting into two small processes, the other three branches are distally acuminate; and ii) saccus is triangular, while in N. inornata it is bilobed with a medial emargination.

Description. Adults. Male. Forewing length 32–39 mm.

Head: Antennae with brown rami; frons pale yellow.

Thorax: Pale yellow. Abdomen dorsally with brown transverse stripes between segments. Anal tufts yellow. Forewings dorsally brown, densely covered with black scales; a dark brown rounded spot on discal cell; six irregular spots on outer margin: two at apical corner; antemedial line arcuate from costal margin to M, then straight from M to inner margin and postmedial line S-shaped, both pale yellow. Hindwings dorsally yellow, scattered with black-brown scales; a brown punctate spot centrally on crossveins; marginal scales yellow. Ventral side of wings uniformly yellow.

Male genitalia:Uncus digitiform, strongly sclerotised.Tegumen L-shaped.Valva distally sclerotised, trifurcated. Dorsal branch long and stout; middle branch slender, with the tip bent outward; ventral branch shorter and pointed, triangular. Valva longer than phallus. Phallus narrow medially, thickened at both basal and distal ends; vesica with hook-like sclerotised spine at base.

Female. Similar to male. Forewing length 52–53 mm.

Head: Antennae rami brown. Frons yellowish-brown.

Thorax: Abdomen dorsally dark brownish-yellow, ventrally light brownish-yellow. Anal tufts dark yellow. Venter of both wings brown. Forewings venter with six irregular yellow spots along outer margin; hindwings venter with yellow marginal band.

Female genitalia: Anal papillae elongate, ear-like. Anterior apophysis ≈2 × length of posterior apophysis. Length of eighth abdominal segment equal to 0.5× anal papillae length. Sterigma elongate-labiate in shape, and strongly sclerotised. Ductus bursae broad and approximately 0.7× the length of corpus bursae. Corpus bursae pyriform. Signum heavily sclerotised, filiform-labiate.

Distribution. The new species is known only from Linzhi, Xizang, China.

Etymology. The specific epithet wui honors Chunsheng Wu (1960–2024), a professor in the Institute of Zoology, Chinese Academy of Sciences, who greatly contributed to the Lepidoptera taxonomy in China. A noun in the genitive case.