Darnilia intermedia Long & van Achterberg, sp. n.

(Figs 12–22)

Material. Holotype, female, ‘ Rog. 1028’ (VNMN), NE. Vietnam: Tuyen Quang, Na Hang, Son Phu, forest, MT, 22°17’32.0’’N 105°28’19.9’’E, 573m, 5.vi.2017, KDLong . Paratypes: 5 females, ‘ Rog. 283’ (IEBR), NW. Vietnam: Hoa Binh, Yen Thuy, Hang Tram, orchard, MT, 20°23’47’’N 105°36’14’’E, 55m, 1-10.ix.2002, KDLong ; ‘ Rog. 1029’ (VNMN), NE. Vietnam: Tuyen Quang, Na Hang, Son Phu, forest, MT, 22°17’32.0’’N 105°28’19.9’’E, 573m, 5.vi.2017, KDLong ; Rog. 1042’ (VNMN), Rog. 1043’ (RMNH), ibid. but 25.viii.2017, KDLong ; ‘ Rog. 1019’(IEBR), NE. Vietnam: Tuyen Quang, Na Hang, Son Phu, forest, MT, 22°17’32.0’’N 105°28’19.9’’E, 573m, 5.vi.2017, KDLong ; 3 females (RMNH, IEBR), N. Vietnam: Ninh Binh, Cuc Phuong N.P., [Malaise trap] in centre, c. 225 m, 29.vi.–18.vii.2000, Mai Phu Quy, RMNH’01 ; 1 female (RMNH), id., but 15.iii-14.iv.2000; 2 females (RMNH, IEBR), id., but 15-27.v.2000; 2 females (RMNH, IEBR), id., but 20.xii.1999 - 10.ii.2000; 2 females (RMNH, IEBR), id., but 18.vii-18.viii.2000; 1 female (IEBR), id., but 1.xi-20.xii.2000; 2 females (RMNH, IEBR), id., but 1-15.v.2000, Malaise trap near entrance; 1 female (RMNH), id., but 15-27.v.2000; 1 female (RMNH), C. Vietnam: Thua Thien Hué, Phong Dién N.R., near base camp, 15 km W of Phong My, 80-120 m, 23.iii-6.iv.2001, Malaise traps, C. v. Achterberg & R. de Vries, RMNH’01 ; 2 females (RMNH), C. Vietnam: Ha Tinh, Vu Quang N.P., 53 m, N 18°21’02’’ E105°26’34’’, 22.ix-6.x.2009, Mal . trap 8 & 10, 53 m, 22.ix-6.x.2009, C. v. Achterberg & R. de Vries, RMNH’09; 2 females (RMNH, IEBR), id., but 135 m, Taiwan trap 16, N18°17’41’’ E105°25’36’’, 24.ix-5.x.2009.

Comparative diagnosis. Antenna long, apical antennomere acuminate; occipital carina more or less widely interrupted medio-dorsally; vein 1-M of fore wing slightly curved basally; vein cu-a oblique; vein 1-M of hind wing 1.7–2.2 × as long as vein M+CU; propodeum with short or medium-sized median carina; first metasomal tergite with median carina in 0.5 basal tergite, 1.2–1.4 × as long as its apical width; second tergite often with median carina in basal 0.3-0.4 of tergite; surface of first-third tergites finely striate, granulate between striae.

Description. Holotype, female, body length 4.2 mm, fore wing length 4.0 mm; antenna 7.3 mm; ovipositor sheath 0.5 mm (Fig. 12).

Head. Antenna with 47 antennomeres; middle antennomere 2.5 × longer than wide (5:2); third antennomere 1.1 × fourth (8:7); preapical antennomere as long as apical antennomere; maxillary palp 1.4 × as long as height of head (34:25); width of face 0.9 × length of face and clypeus combined (15:17); malar space 1.25 × as long as mandible basal width (5:4); mandible basal width 0.6 × as long as hypoclypeal depression (4:7); malar suture present (Fig. 14); distance between tentorial pits 3.2 × distance between pits and eyes (8:2.5); in dorsal view, height of eye 5.0 × as long as temple (15:3) (Fig. 13); in lateral view, width of eye 3.25 × as long as temple (13:4) (Fig. 15); ocelli medium sized, POL:OD:OOL=2:3:3; distance between front and hind ocelli 0.7 × as long as OOL (2:3) (Fig. 13). Face rugo-punctate; frons almost flat, smooth; vertex with fine transverse striae; temple smooth.

Mesosoma. Length of mesosoma 1.45 × as long as high (58:40); pronotal side finely granulate anteriorly, smooth ventrally; mesoscutum smooth; notauli narrow, rather deep anteriorly, flat posteriorly (Fig. 16); prescutellar sulcus with one median carina, 0.5 × as long as scutellum (4:8); scutellum coriaceous; mesopleuron and precoxal sulcus smooth (Fig. 18); metapleuron finely granulate; propodeum with short subbasal median carina, granulate with some divergent striae medio-posteriorly (Fig. 20).

Wings. Fore wing: length 3.2 × its maximum width (119:37); pterostigma 3.4 × as long as wide (34:10); vein r arising before middle of pterostigma; r:2-SR:3-SR:SR1=7:11:19:34; vein 1-M slightty curved basally; vein cu-a oblique, 1-CU1:cu-a:2-CU1:3-CU1=3:5:20:4; length of second submarginal 2.9 × as long as its apical width (26:9). Hind wing: length 4.7 × its maximum width (90:19); vein 1-M 1.9 × as long as vein M+CU (Fig. 22); vein M+CU:1-M: 1r-m=15:29:8.

Legs. Length of hind femur, tibia and basitarsus 4.4, 9.2 and 8.0 × their maximum width, respectively; inner hind tibial spur 0.25 × as long as basitarsus (6:24); hind basitarsus 0.6 × second-fifth tarsus (24:41); fourth hind tarsus 0.8 × telotarsus (7:9); hind tarsal claw large, setose (Fig. 17).

Metasoma. First tergite 1.4 × as long as apical width (33:23) (Fig. 21); median length of second tergite 1.85 × than third (24:13); ovipositor sheath 0.75 × as long as hind basitarsus (18:24) and 0.12 × fore wing; ovipositor slender. First metasomal tergite with fine median carina in 0.5 basal tergite, surface of the first tergite granulate but finely striate laterally; second tergite with median carina in 0.3-0.4 basal tergite (Fig. 21); surface of second-third tergites finely striate with granulation (Fig. 21).

Colour. Pale yellow; scapus and antenna yellow; palpi pale yellow; stemmaticum brown; pronotal side brown dorsally, pale yellow ventrally; mesopleuron and metapleuron pale yellow; mesoscutum yellow; tegula and scutellum pale yellow; propodeum dark brown but yellow subapically (Fig. 20); fore and middle legs pale yellow; hind leg yellow except hind coxa pale yellow; fore wing vein brownish yellow; pterostigma yellow basally and apically, brownish medially; first metasomal tergite brown basally and laterally, brownish yellow medio-apically; second-fourth tergites yellow medially, brown laterally, whitish yellow latero-ventrally (Fig. 21).

Male: Unknown.

Etymology. From “inter” (Latin for between), because this species is intermediate between Darnilia granulata, sp. n. and D. vietnamica, sp. n.

Host: Unknown.

Variation. Paratypes: females, antenna with 40–50 segments; first tergite 1.2–1.4 × as long as apical width; body length 3.7–4.7 mm; fore wing length 3.5–4.4 mm; vein 1-M of hind wing 1.7–2.2 × as long as vein M+CU.

Notes. Darnilia intermedia sp. n. can be distinguished from D. granulata sp. n. and D. vietnamica sp. n. by the above key. Besides, D. intermedia differs from both D. granulata and D. vietnamica by having the following characters: a) surface of second-third metasomal tergites with fine longitudinal striae (finely granulate in D. granulata, and largely striate in D. vietnamica); b) occipital carina more or less broadly interrupted medio-dorsally. Additionally, D. intermedia can be separated from D. granulata by having: a) vein 1-M of hind wing 1.7–2.2 × as long as vein M+CU (1.1–1.6 × in D. granulata); b) first metasomal tergite with basal median carina in 0.4–0.5 tergite (without median carina in D. granulata).