Synanthedon ceraunus sp. nov.

(Figs 12, 13, 22, 28)

Holotype. ♂,TAICHUNG: Heping, Malunshan, 1200 m, 16.III.2014, reared from C. fargesii, emg. 20.IV.2014, HSUM 14C49M, J.Y. Liang Coll. (NHM). Paratypes. 1 ♀, same date as holotype, J.Y. Liang Coll. (NTNU); 1 ♂, 1 ♀, same locality, 1200 m, 10.III.2013, reared from C. fargesii, emg. 12−19.IV.2013, HSUM 13C24M, J.Y. Liang Coll. (♂, Gen. Prep. JYL-015, CAK) (♀, Gen. Prep. JYL-014, NYNU); 1 ♀, CHIAYI: Zhuqi, Dadongshan, 1700 m, 20.I.2014, reared from C. cuspidata, emg. 13.III.2014, HSUM 14A43M, J.Y. Liang Coll. (NTNU); 1 ♀, YILAN: Nanao, Lankanshan, 1300 m, 30.IV.2014, reared from L. kawakamii, emg. 21.V.2014, HSUM 14D116M, J.Y. Liang Coll. (NTNU).

Description. Male (Fig. 12). Antennae length 6.4−6.8mm (n=2); forewing length 8.6 −9.1 mm (n=2); body length 11.1−11.5 mm (n=2). Head: antenna black with blue sheen; frons white; labial palpus black, white ventrally; vertex black with blue sheen; pericephalic scales white with a few black and white scales dorsally. Thorax: patagium bluish black with blue sheen; tegula and mesothorax blue with sheen; metathorax blue with a few white scales. Legs: fore coxa bluish black with laterally white;fore femur and tibia black with blue sheen; fore tarsus ventrally white with a few dark gray scales, dorsally black with some white spot on each tarsomere basally; hind tibia bluish black with blue sheen, internally and at base of both pairs of spurs white; hind tarsus ventrally ash white with a some white spot on each tarsomere basally, dorsally black with blue sheen; spurs white, internally black. Abdomen: blue with sheen; tergite 2 with a narrow white stripe distally; sterna bluish black; anal tuft dorsally black with blue sheen, ventrally black. Forewing: basally blue with sheen; costal margin, discal spot and veins within exterior transparent area black with blue sheen; apical area dark brown; discal spot slightly broadened medially; exterior transparent area large divided into six cells, level to M2 about 3X as broad as discal spot and 0.5X as broad as apical area; posterior transparent area reaching over of discal spot; fringe dark brown. Hindwing: transparent; veins, discal spot and outer margin dark brown to black with bronzed-blue sheen; discal spot small, cuneiform, reaching to vein M2; fringe dark brown to black.

Female (Fig. 13). Antennae length 6.4−7.1mm (n=4); forewing length 8.4−9.5 mm (n=4); body length 10.8−11.4 mm (n=4). Similar to male. The female differs from male by the abdomen tergite 4 with a few white scales dorsally, and sterna 4 with a narrow white stripe distally.

Genitalia. Male (Gen. Prep. JYL-15, NTNU, Fig. 22). Tegumen-uncus complex broad; scopula androconialis well-developed, long, about 3/4 length of tegumen-uncus complex; crista gnathi lateralis large, semioval; crista gnathi medialis long, somewhat broader than crista gnathi lateralis, with distal margin divided into two narrow cristae; valva elongated trapeziform; crista sacculi oblique, pocket-shaped, gradually lowered posteriorly, covered with dense, strong, bifurcate setae; saccus with a bifurcate base, slightly broadened basally, about 0.5X shorter than vinculum; phallus relatively narrow, about 0.8X as short as valva, slightly broadened subdistally, with numerous small tooth ventro distally; vesica without cornuti.

Female (Gen. Prep. JYL-14, NTNU, Fig. 28). Eighth sclerite relatively large and broad; posterior apophysis long, about 1.3X as long as anterior apophysis; antrum well-sclerotized, large, broad, funnel-shaped, with a deep oval cut ventrally; ductus bursae narrow, long, membranous; corpus bursae membranous, ovoid, without signum.

Diagnosis. A distinctive species, with body ground color mostly black with blue sheen. This species possesses genitalia similar to S. spheciformis (Denis & Schiffermüller 1775) from Europe and central Asia, but valva of the latter is considerable shorter and strongly convex dorsally.

Etymology. A noun of Latin, ceraunus = meteor.

Biology. The larva bores into the stem or trunks of 1−2 cm in diameter of Castanopsis and Lithocarpus (Fagaceae) and feeds on callus tissue around the entrance hole, which is covered with silk, debris, and frass.

Distribution. Known only from Taiwan.