Opostega apicidissecta, Sun & Wang, 2025

Opostega apicidissecta sp. nov.

urn:lsid:zoobank.org:act:8A17CED0-E89F-467D-93CF-54571F4B5E4F

( Figs 1, 3 View FIGURES 1–4 )

Type material. Holotype. [ CHINA] ♂, Beitun , 512 m, Xinjiang, 20 vii 2007, leg. XP Wang et al., slide No. SH21196 .

Diagnosis. The new species is similar to O. spatulella Herrich-Schäffer, 1855 and O. magnirotunda sp. nov. in male genitalia. It can be distinguished from them by the presence of an aedeagus, which is absent in both comparison species. It further differs from O. spatulella by the forewing without a dark brown apical speckle, and in male genitalia by the hook-shaped costal process of the valva (in O. spatulella , the forewing has a dark brown apical speckle, and the costal process of the valva is almost straight) ( Nieukerken 1990: 368). The new species can be further distinguished from O. magnirotunda by the tegumen-vinculum ring without a round sclerite and the costal margin of the valva almost straight (in O. magnirotunda , the tegumen-vinculum ring has a round sclerite ranging from anterior 2/7 to 3/4, and the costal margin of the valva is sinuate). The differences between O. magnirotunda sp. nov. and O. apicidissecta sp. nov. are stated in the diagnosis of the latter species.

Description. Adult ( Fig. 1 View FIGURES 1–4 ). Male wingspan 8.5 mm.

Head: Vertex and frons cream white. Maxillary palpus white. Labial palpus pale yellow. Antenna with scape white, flagellum brownish yellow. Collar cream white.

Thorax: Mesonotum pale yellow, with scattered brown scales; tegula pale yellow. Forewing ground color pale yellow, tinged with silvery white luster; costal spot brown, extending from distal 2/5 of costal margin downward to distal 1/4 of vein M; dorsal spot brown, beyond middle of dorsum; fringe pale yellow, mixed with brown scales. Hindwing silvery white; fringe pale yellow. Foreleg brownish bronzy except tarsus yellow; midleg silvery white; hindleg yellow.

Abdomen: Yellowish brown.

Male genitalia ( Fig. 3 View FIGURES 1–4 ). Uncus lobes semicircular, setose posteriorly. Tegumen-vinculum ring inflated posterolaterally, uniformly slender anteriorly. Gnathos with a semicircular anteromedial emargination; basal arm wide, heavily sclerotized, shorter than mesial process; mesial process tapered to pointed apex. Valva with main body subovate, costal margin almost straight, ventral margin broadly rounded; costal process 0.41 × length of valva, narrowed to obtusely rounded apex; pedicel 0.17 × length of valva, widened towards cucullar lobe; cucullar lobe 1.9 × width of pedicel, with dense setae, pectinifer with 27 blunt spines. Aedeagus 0.62 × length of tegumen-vinculum ring, slightly arched. Juxta 1.4 × length of aedeagus, distal 1/3 inflated laterally, apex deeply concave at middle, forming two large distal lobes.

Female unknown.

Distribution. China (Xinjiang).

Etymology. The specific epithet is derived from the Latin apic - and dissectus, referring to the juxta deeply concave medioapically.