Dilar yangyingae, Li & Liu, 2025

Dilar yangyingae sp. nov.

Fig. 9 Common name. 杨英栉角蛉 View Figure 9

Diagnosis.

The new species is characterised by the forewing with dense and scattered spots throughout (Fig. 9 A View Figure 9 ), by the male ectoproct posterodorsally with a pair of slender elongate projections which are almost half the length of the whole ectoproct (Fig. 9 C, I View Figure 9 ), by the extremely short male gonocoxite 9, which is only as one-fifth as long as gonocoxite 10 (Fig. 9 D, I View Figure 9 ) and by the narrow, falcate male gonocoxite 10 (Fig. 9 D, J View Figure 9 ).

Description.

Male. Body length 6.0 mm; forewing length 9.7 mm, hindwing length 8.0 mm.

Head generally brown, with yellowish-brown setose tubercles; vertex pale brown. Compound eyes blackish-brown. Antenna brown; flagellum pectinate, medial branches longer than those branches at base, longest branch nearly 4.0 times as long as corresponding flagellomere, distal seven flagellomeres simple.

Thorax brown; pronotum with a pair of yellow ovoid tubercles at middle, tubercles surrounded by dark brown markings; mesonotum dark brown at middle, as well as along anterior and lateral margins, submedially with a pair of dark brown oblique stripes; metanotum much paler than mesonotum. Legs pale brown, femora, tibiae and each tarsomere dark brown at tip. Wings hyaline, slightly smoky brown (Fig. 9 A View Figure 9 ). Forewing 2.3 times as long as wide, with dense and scattered spots throughout; markings darker on base; three and two nygmata, respectively present on left and right forewing, at base and middle, nygmata respectively surrounded by a brownish spot; longitudinal veins pale yellow, interrupted by many brown spots; crossveins pale brown. Hindwing 2.2 times as long as wide, almost immaculate.

Abdomen brown. Tergum 9 in dorsal view with an arcuate incision, a nearly V-shaped posterior incision, leaving a pair of hemitergites, which are obtuse distally and densely setose. Sternum 9 nearly trapezoidal, only one third in length of tergum 9, almost truncate posteriad (Fig. 9 D, J View Figure 9 ). Ectoproct in dorsal view nearly rectangular, posterodorsally with a pair of slender elongate projections, almost half length of the whole ectoproct, each projection distally accompanied with a tiny lateral unguiform projection (Fig. 9 C, I View Figure 9 ); posteroventrally with two pairs of digitiform projections and a pair of bifid unguiform projections (Fig. 9 D, J, L View Figure 9 ). Gonocoxite 9 small, subtriangular, slightly extended transversely (Fig. 9 D, I View Figure 9 ). Gonocoxite 10 slender elongate, almost five times as long as gonocoxite 9, falcate, with pointed base and tip (Fig. 9 D, J View Figure 9 ). Fused gonocoxites 11 nearly beam-shaped, slightly anteriorly convex, laterally connecting to bases of gonocoxites 9 (Fig. 9 D, I View Figure 9 ). Hypandrium internum nearly trapezoidal, with lateral margins slightly arcuate (Fig. 9 D, J View Figure 9 ).

Female. Body length 5.0 mm; forewing length 10.0 mm, hindwing length 9.0 mm.

Wings with markings much darker than those in male (Fig. 9 B View Figure 9 ).

Sternum 7 in lateral view nearly rectangular, in ventral view nearly rectangular, with posterior margin almost truncate. Segment 8 ventrally without subgenitale. Tergum 9 in lateral view as wide as tergum 8. Bursa copulatrix in lateral view irregularly sac-like, with a distinct ridge present at the upper-middle part (Fig. 9 G, M View Figure 9 ) and in ventral view, as an arcuate structure bearing a pair of oppositely curved, crescent-shaped lobes (Fig. 9 H, N View Figure 9 ). Colleterial gland tubular and bursal accessory gland not observed. Ectoproct small, ovoid (Fig. 9 G, M View Figure 9 ).

Materials examined.

Holotype ♂, China • Hubei Province, Muyu Town, Mt. Laojunshan [木鱼镇老君山], 1290 m alt., 11. VII. 2021, Yangying ( CAU) . Paratype • 1 ♀, same data as holotype ( CAU) .

Etymology.

The species is dedicated to Ms. Ying Yang, who is a friend of the first author and collected the type specimens.

Distribution.

China ( Hubei).

Remarks.

The new species is possibly a member of the D. hastatus species-group, based on the slender elongate male gonocoxite 10. Compared to other species in this group, the new species appears to be related to D. sinicus , as they share a similar shape of the male gonocoxite 9, which is subtriangular and extremely short. However, the new species is distinguished by a unique feature of the male ectoproct, which posterodorsally bears a pair of slender, elongate digitiform projections, nearly half the length of the entire ectoproct (Fig. 9 I View Figure 9 ). In contrast, the posterodorsal projections in other members of the D. hastatus species-group, as well as in all other species of Dilar , are much shorter.