Periacma solitaridens 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 : 118

Periacma solitaridens Wang , sp. nov.

( Figs 17 , 31 )

Type material. CHINA, Sichuan: Holotype ♂, Hailuogou (29.36ºN, 102.6ºE), Luding , 1695 m, 30.VI.2016, leg. KJ Teng & XF Yang, slide No. XZX20615 . Paratype: 1♂, sama data as holotype .

Diagnosis. The new species is similar to P. kangdingensis Wang & Li, 2002 and P. fengxianensis Wang & Zheng, 1995 in male genitalia. It can be distinguished from P. kangdingensis by the uncus distinctly widened from basal 1/3 to a broadly rounded apex, the costal part of the valva elliptical distally, and the sacculus half as long as the costal part of the valva; in P. kangdingensis , the uncus is slightly widened to the obtuse apex, the costal part of the valva is subparallel distally, and the sacculus is longer than half the length of the costal part of the valva. The new species can be distinguished from P. fengxianensis by the basal width of the uncus less than 1/2 of its widest part, and the aedeagus with a preapical denticle on one side; in P. fengxianensis , the basal width of the uncus is more than 1/2 of its widest part, and the aedeagus has several denticles laterodistally.

Description. Adult ( Fig. 17 ). Wingspan 16.0 mm.

Head. Vertex and frons yellow. Labial palpus yellow, second segment with distal 2/3 black on outer surface. Antenna with scape white on ventral surface, dark brown on dorsal surface; flagellum yellow on ventral surface, black with fine yellow annuli on dorsal surface.

Thorax. Mesonotum dark brown, surrounded by yellow scales; tegula yellow, with dense dark brown scales basally. Forewing yellow, with brown scales denser distally and between fold and dorsum; costal margin dark brown in basal 1/6; dorsum with a large dark brown spot near base; dark brown speckle along above fold to middle of cell; discal spot dark brown, above preceding speckle; postmedial fascia dark brown, extending from about costal 2/3 to tornus, narrower medially; fringe yellow. Hindwing and fringe grey. Legs yellow, except three distal tarsomeres of fore- and midlegs black; on dorsal surface, foreleg with femur black, midleg with black scales on femur, tibiae of fore- and midlegs black, tarsi black at middle of first tarsomere and at base of second tarsomere; on outer surface, hindleg with tarsus black at base of each tarsomere except first tarsomere.

Male genitalia ( Fig. 31 ). Uncus narrow and parallel sided in basal 1/3, with long setae at basal 1/6 laterally, inflated from basal 1/3 to broadly rounded apex. Gnathos with basal arm gradually widened; ventral plate narrow and parallel sided posteriorly, widened and spinulous anteriorly, narrowed outward to obtuse end anterolaterally, slightly concave at middle on anterior margin. Valva with costal part uniformly wide from base to basal 2/5, distal 3/5 inflated elliptically, obtusely rounded at apex; costa straight basally, arched distally; dorso-proximal process dilated distally, setose; sacculus about half length of costal part of valva, wide at base, narrowed to middle length, sharply produced from middle to a slender, apex-pointed process bent inward distally. Saccus short, trapezoidal. Aedeagus about half length of costal part of valva, gradually widened from base to 1/2, then tapered to before apex; apex widened, with a denticle before apex.

Female unknown.

Distribution. China (Sichuan).

Etymology. The specific epithet is derived from the Latin solitarius and –dens, referring to the aedeagus with a single denticle.

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 29‒32. Male genitalia of Periacma spp.29.P.nepalensis, slide No. XZX20769; 30. P. securiformis sp. nov., holotype, slide No. LiSR16146; 31. P. solitaridens sp. nov., holotype, slide No. XZX20615; 32. P. subaequalis sp. nov., holotype, slide No. XZX20520. Scales = 0.2 mm.