Megalommum hoabinhense Dzuong & Long & Mai & Hoa & Oanh & Nghiep 2022, sp. nov.

Megalommum hoabinhense Long, sp. nov.

Figs 1–11

Diagnosis. In dorsal view, head 1.6 × as wide as long; eye length 4.9 × temple; and eye length 1.7 × its width; ocelli in high triangle, POL: OD: OOL= 3: 5: 4 (Fig. 3); vein 1-M of fore wing thin, 0.9 × vein 1-CU1 (Fig. 5); vein m-cu slightly curved inwards, and 1.2 × vein 1-M; basal length of second submarginal cell 4.3 × apical width; in lateral view, mesosoma 1.9 × its height; hind femur robust, 3.2 × its maximum width (Fig. 9); mesoscutum flat posteriorly, with sparse fine punctures (Fig. 7); first metasomal tergite length 1.5 × its apical width, with median area striate-rugulose in most part, coriaceous apically; second tergite finely sculptured; midbasal triangular area of second tergite smooth, with punctate convergent grooves (Fig. 8); second metasomal suture crenulate medially; third tergite sculptured laterally, smooth medially; ovipositor straight (Fig. 10); ovipositor sheath obliquely setose, 0.2 × as long as fore wing.

Material examined. Holotype, ♀, “Bracn. 094 ” (IEBR), NW Vietnam: Hoa Binh, Bao Hieu, litchi+sugarcane orchard, MT, 20°23’N 105°34’E, 80 m, 01–10.viii.2003, KD Long.

Description. Holotype, female, length of body 7.0 mm, fore wing 8.1 mm, antenna 8.4 mm, ovipositor sheath 1.9 mm (Fig. 1).

Head. Antenna with 62 flagellomeres, slightly longer fore wing; apical antennomere with distinct spine; in lateral view, scapus 1.6 × as long as wide; length of first flagellomere 1.1 × second; first, second and penultimate flagellomeres 1.3, 1.2 and 1.7 × their maximum width,; maxillary palp as long as height of head; head 1.3 and 1.6 × as wide as long in anterior (frontal) and dorsal view respectively; face narrowed medially, rugose, 0.6 × as wide as long (15: 24) (Fig. 2); in frontal view, eye length 2.2 × as long as its transverse width (38: 17); clypeus separated from face with a transverse carina; height of clypeus: inter tentorial distance: tentorial ocular distance = 5: 9: 3; distance between tentorial pits 3.0 × as long as distance from tentorial pit to eye margin (Fig. 2); malar space 0.5 × basal width of mandible; in lateral view, transverse width of eye 3.3 × as long as temple (30: 9) (Fig. 4); in dorsal view, length of eye 4.9 × temple (34: 7); eye height 1.7 × its width; ocelli in high triangle, distance between anterior and posterior ocelli as long as OOL; POL: OD: OOL= 3: 5: 4 (Fig. 3); vertex smooth, sparsely punctate, sparsely setose, not emarginated beyond antennal sockets; frons smooth, distinctly depressed laterally, with fine median carina (Fig. 3).

Mesosoma. Mesosoma 1.9 × its height (62: 33); pronotum smooth laterally, setose; mesoscutum flat posteriorly, sparsely setose, with sparse fine punctures medially, almost smooth anteriorly and laterally (Fig. 7); notauli shallow, smooth; scutellar sulcus narrow and shallow, crenulate; scutellum smooth, sparsely setose; mesopleuron and metapleuron smooth, setose; medial area of metanotum without midlongitudinal carina anteriorly; propodeum smooth, setose.

Wings. Fore wing (Fig. 5): length of pterostigma 5.0 × its width; vein 1-SR+M curved subbasally; vein 1-M thin, 0.9 × vein 1-CU1 (17: 18); vein 1-CU1 very thick, 3.0 × as thick as vein 1-M; vein 2-M curved basally; m-cu slightly curved inwards, and 1.2 × vein 1-M (Fig. 5); subdiscal cell distinctly broader than discal cell, with median setose area and narrow glabrous sclerome, and upper and posterior parts of this area glabrous; veins SR1 curved subbasally; ratio of length of veins r: 3-RS: SR1 = 16: 41: 81; 2-RS: 3-RS: r-m = 24: 41: 15; second submarginal cell slightly narrowed apically, basal length of second submarginal cell 4.3 × its apical width; vein CU1b triangular, strongly widened basally (Fig. 5); subdiscal (brachial) cell with median area setose, surround this area glabrous. Hind wing (Fig. 6): vein SR slightly curved subbasally, parallel-sided apically; subbasal cell setose; vein 1r-m almost straight; vein 2-SC+R vertical (Fig. 6); vein 1-M widely curved basally (Fig. 6); M+CU: 1-M: 1r-m = 13: 83: 26; apex of vein SC+R1 with three curved hamuli.

Legs. Fore tibia 0.75 × fore tarsus (43: 57); ratio of lengths of fore femur: tibia: basitarsus: hind tarsus = 29: 43: 20: 57; hind femur robust, 3.2 × its maximum width (Fig. 9); femur, tibia, basitarsus 3.2, 10.9 and 6.0 × their maximum width; outer and inner hind tibial spurs 0.35 × and 0.4 × as long as hind basitarsus; respectively; tarsal claw simple and with bristly ventrally.

Metasoma. First metasomal tergite 1.5 × as long as wide apically (41: 28), distinctly rugose with a midlongitudinal carina and a pair of narrow lateral smooth grooves; median area striate-rugulose in most part, coriaceous apically (Fig. 11); second metasomal tergite 1.2 × as long as third tergite medially (25: 21), 1.4 × as wide (basally) as long (35: 25), length of midbasal triangular of second tergite in basal 0.8 of tergite (19: 25) (Fig. 8); lateral sides of midbasal triangular area surrounded by shallow convergent punctate grooves; antero-lateral depression wide, coriaceous (Fig. 8); second metasomal suture narrow, crenulate; third-fifth metasomal tergites coriaceous; ovipositor straight, needle-shaped apically, without dorsal notch or nodus and ventral serrations (Fig. 10); ovipositor sheath covered with dense oblique setae, 0.2 × as long as fore wing.

Colour. Body yellow (Fig. 1); eyes black or dark brown; scapus and pedicellus yellow; flagellum dark brown in more than basal half, brownish yellow apically; pterostigma yellow with black spot apically; vein and membrane of fore wing yellow, except parastigma black and dark brown area between parastigma and base of vein 1-SR+M; all legs yellow; ovipositor sheath brown; ovipositor yellow.

Distribution. NW Vietnam (Hoa Binh).

Biology. Unknown.

Etymology. The new species is named after the province (Hoa Binh), where the holotype was discovered.