Stenopsocus tibialis Banks

(Figs. 15–16)

Stenopsocus tibialis Banks, 1937: 259 . Type locality: China (Taiwan: Arisan, Taiheizan).

Diagnosis. This species is characterized by forewing without setae on Cu2, yellowish pterostigma, R1 with narrowly brown stripe and R without markings.

Adult male. Body (Fig. 15 a) length 2.89 mm, length from postclypeus to wing tip 5.12 mm. IO: 0.31 mm, d: 0.27 mm, IO/d=1.15, f1: 0.95 mm, f2: 0.72 mm, f3: 0.63 mm, FWL: 4.07 mm, FWW: 1.51 mm, HWL: 2.99 mm, HWW: 0.99 mm, t1: 0.46 mm, t2: 0.13 mm.

Colour (in alcohol). Head (Figs. 15 c, d) dark brown, with a subtrapezoidal yellowish brown area. Postclypeus dark brown, labrum laterally much paler, apex of maxillary palpus brown, remaining segments of maxillary palpus whitish. Thorax dark brown. Legs pale yellow, with apices of femur, tibiae and tarsomeres brown.

Forewing (Fig. 15 g) transparent, Sc and R dark brown, anterior margin of pterostigma and 1A yellow, R1 dark brown with narrow dark brown marking, not connecting to Rs. Hindwing (Fig. 15 h) immaculate.

Genital segments (Figs. 16 a–d) strongly sclerotized. Epiproct (Fig. 16 b) subtriangular. Paraproct sclerotized around trichobothria, with 23 trichobothria. Endophallus (Fig. 16 c) strongly sclerotized, external parameres robust with some punctures on broadened apex, and not exceeding apex of aedeagal arch; aedeagal arch narrow. Hypandrium (Fig. 16 d) strongly sclerotized, with round margin.

Adult female. Body (Fig. 15 b) length 3.00 mm, length from postclypeus to wing tip 5.42 mm. IO: 0.47 mm, d: 0.22 mm, IO/d=2.14, f1: 1.07 mm, f2: 0.75 mm, f3: 0.57 mm, FWL: 4.07 mm, FWW: 1.51 mm, HWL: 2.99 mm, HWW: 0.99 mm, t1: 0.46 mm, t2: 0.13 mm.

Colour similar to male, but slightly darker. Vertex with a yellowish rectangular area. Abdomen with 1–2 segments reddish brown, and with 3–7 segments dorsally reddish brown, genital segments dark brown. Wings similar to male.

Genital segments (Figs. 16 e–i) strongly sclerotized. Epiproct (Fig. 16 f) subtriangular. Paraproct with 22 trichobothria. External valve (Fig. 16 h) short, with a narrow apex. Sclerotized area of subgenital plate (Fig. 16 g) connecting with a narrow, sclerotized region along distal margin of subgenital plate.

Specimens examined. CHINA (TAIWAN): Hualien, Pi-lu Sacred Tree (2150 m), 5 males, 5 females, 6.vi.2013, Liang Feiyang.

Distribution. China (Taiwan).