Periacma aduncata Wang

Yin, Aihui & Wang, Shuxia, 2014, Species of Periacma, Irepacma and Epiracma from Taiwan (Lepidoptera: Oecophoridae), Zootaxa 3835 (2), pp. 283-291 : 284-285

Periacma aduncata Wang , sp. nov.

( Figs. 1 , 7 , 12 )

Type material. Holotype: ♂, Taiwan: Taihoku, 10 May 1935, coll. S. Issiki, genitalia slide No. 142393( USNM). Paratype: 1 ♀, same data as holotype except dated 7 May 1935 ( USNM).

Diagnosis. Periacma aduncata is similar to P. sinica Wang, Li et Liu, 2001 both in appearance and in genitalia. It can be distinguished from the latter by the forewing having a discontinuous fascia; the uncus with distal 2/5 expanded in a fan shape, the gnathos with widest part 1.1 times its length, and the valva with widest part about twice the width of the narrowest part at base in the male genitalia; and the apophysis anterioris that is less than 1/3 length of the apophysis posterioris in the female genitalia. In P. sinica , the forewing has a continuous brown fascia; the uncus is expanded roundly in distal 1/3, the widest part of the gnathos is 1.3 times its length, and the widest part of the valva is about 1.5 times width of the narrowest part at base; and the apophysis anterioris is more than 1/3 length of the apophysis posterioris.

Description. Imago ( Fig. 1 ). Wingspan 15.0−17.0 mm. Body orange yellow. Antenna with flagellum annulated with pale brown streaks on dorsal surface. Forewing with costal margin gently arched, dorsum almost straight, apex bluntly rounded; discontinuous brown fascia extending from beyond middle of costal margin to end of fold; brown spot at basal 1/3 and 3/5 of cell and at distal 2/5 of fold, respectively; cilia pale yellow. Hindwing and cilia pale gray. Fore- and midlegs orange yellow, speckled with brown on tarsi; hindlegs tinged with brown scales on tarsi.

Male genitalia ( Fig. 7 ). Uncus with basal 3/5 narrow, nearly parallel laterally, distal 2/5 expanded in a fan shape. Gnathos with basal half trapezoid, slightly widened from base to middle; distal half triangular, gradually narrowed to bluntly rounded apex, with long dense spines. Tegumen broad, inverted V shape. Valva elongate elliptical; basal 1/3 narrow, about same width; distal 2/3 gradually widened to before a slightly narrowed apex; widest part about twice width of narrowest part at base; dorsal-proximal process rod-like, setose, slightly dilated distally. Sacculus broad basally, distinctly narrowed to 3/5, distal 2/5 finger-like; with triangular process at ventral 1/4 and 3/4, respectively, the former distinctly larger than the latter. Saccus nearly semicircular. Aedeagus with basal 1/3 rod-like, gradually widened from basal 1/3 to 1/2, with a hooked process medially; distal 1/2 gradually narrowed to pointed apex, with teeth.

Female genitalia ( Fig. 12 ). Papilla analis setose, broad basally, gradually narrowed distally, forming an acute apex. Apophysis anterioris less than 1/3 length of apophysis posterioris. Lamella postvaginalis weakly sclerotized, with dense spinules, sinuate along posterior margin; lamella antevaginalis band-like, curved, with triangular plate laterally. Ductus bursae with posterior 1/3 sclerotized, anterior 2/3 membranous, widened. Corpus bursae rounded, longer than ductus bursae; sigmum thorn-like, curved, rounded at base.

Distribution. China ( Taiwan).

Etymology. The specific name is from the Latin aduncatus, referring to the hooked process of the aedeagus.

Figures

FIGURES 1 − 6. Adults of Periacma, Irepacma and Epiracma spp. 1. P. aduncata sp. nov., paratype, female; 2. I. conioxantha comb. nov. male; 3. I. flagellata sp. nov., holotype, male; 4. Head of I. flagellata sp. nov., paratype, male; 5. E. longicaudata sp. nov., holotype, male; 6. E. annularis sp. nov., holotype, male. (Scales: 1 - 3, 5 - 6 = 2.0 mm; 4 = 0.5 mm).

FIGURES 7 − 11. Male genitalia of Periacma, Irepacma and Epiracma spp. 7. P. aduncata sp. nov., holotype, slide no. 142393; 8. I. conioxantha comb. nov.; 9. I. flagellata sp. nov., holotype, slide no. 142399; 10. E. longicaudata sp. nov., holotype, slide no. YAH 13065; 11. E. annularis sp. nov., slide no. 142403. (Scales = 0.5 mm).

FIGURES 12 − 15. Female Genitalia of Periacma, Irepacma and Epiracma spp. 12. P. aduncata sp. nov., paratype, slide no. 142409; 13. I. conioxantha comb. nov.; 14. I. flagellata sp. nov., paratype, slide no. YAH 13062; 15. E. annularis sp. nov., paratype, slide no. 142404. (Scales = 0.5 mm).