Streblocera (Eutanycerus) tuyenquangensis Long, 2020

Long, Khuat Dang & Nhi, Pham Thi, 2020, Notes on the genus Streblocera Westwood, 1883 (Hymenoptera: Braconidae: Euphorinae) from Vietnam, with description of four new species, Zootaxa 4767 (3), pp. 402-414 : 411-414

Streblocera (Eutanycerus) tuyenquangensis Long , sp. n.

( Figs 34–45 )

Material examined. Holotype, ♀, “Euph. 332” ( IEBR), NE Vietnam: Tuyen Quang, Na Hang, Thanh Tuong , forest, MT, 22°19’01’’N 105°24’02’’E, 162m, 25.xii.2016, KDLong.

Diagnosis. Antenna with 23 antennomeres; scapus long, with tooth-shaped horn in basal 0.2 of scapus ( Fig. 41 ); length of scapus 9.3 × its maximum width, and 2.2 × of head height (in dorsal view); tentorial pits at lower level of eyes ( Fig. 36 ); malar space 1.2 × as long as basal width of mandible; mesosoma of mesosoma 1.8 × as long as its height; propodeum with short basal carina, smooth basally, largely areolate; first metasomal slightly narrowed behind spiracle, length of first metasomal tergite 2.3 × as long as its apical width; length of fore wing 0.8 × as long as body.

This new species is close to S. pila , but can be distinguished be having scapus slender, ventral tooth-shaped tubercle in basal 0.2 of scapus (0.3 in S. pila ); apical width of first tergite 3.75 × its minimum width (3.0 × in S. pila ); antenna with 23 antennomeres.

Description. Holotype, ♀, body length 4.8 mm, fore wing length 3.9 mm, ovipositor sheath 0.5 mm ( Fig. 34 ).

Head. Antenna with 23 antennomeres; scapus long, length of scapus 9.3 × its maximum width (65: 7), with tooth-shaped horn in basal 0.2 of scapus (15: 65); scapus 2.2 × of head height (65: 30); third antennomere 1.3 × fourth (8: 6); second-seventh flagellomeres serrate ventrally ( Fig. 40 ); length from eighth flagellomere to apex of antenna 0.9 × scapus (60: 65); in dorsal view, width of head 1.5 × its median length (44: 30), 1.4 × width of mesoscutum (without tegulae) (44: 31); ocelli small, POL: OD: OOL = 5: 3: 9 ( Fig. 35 ); in lateral view, transverse diameter of eye 1.3 × temple (14: 11); eye as high as broad (14: 14); in frontal view, diameter of antennal socket 0.9 × between sockets (7: 8); face width 0.9 × length of face and clypeus combined (23: 25), and 1.3 × height of eye (23: 18); malar space 1.2 × as long as basal width of mandible (6: 5), and 0.3 × height of eye (6: 19); distance between tentorial pits 1.4 × distance from pit to eye margin (10: 7); face finely and densely punctate ( Fig. 36 ); frons with sparse striae medially, sparsely punctate laterally ( Fig. 35 ); vertex and temple almost smooth, with sparse punctures ( Figs 35, 37 ).

Mesosoma. Length of mesosoma 1.8 × as long as its height (71: 39); notauli deep, largely crenulated ( Fig. 38 ), fused posteriorly with large rugose area close to scutellar sulcus; scutellar sulcus rather wide, 0.6 × as long as scutellum (5: 8), with one carina ( Fig. 38 ); mesoscutum and scutellum highly smooth; subalar depression almost smooth; pronotal side sparsely crenulated anteriorly, smooth ventrally and posteriorly ( Fig. 39 ); precoxal sulcus wide, deep, sparsely crenulate; mesopleuron smooth; metapleuron rugose; propodeum with short basal carina, punctate basally, areolate-rugose medially and apically ( Fig. 43 ).

Wings. Length of fore wing 3.1 × its width (115: 37); length of pterostigma 3.5 × its width (35: 10), and 1.3 × vein 1-R1 (35: 26) ( Fig. 44 ); vein r arising just behind middle of pterostigma, 0.1 × as long as width of pterostigma (5: 35), and 0.2 × vein 1-R1 (5: 26); vein 1-CU1 thick, 1-CU1: cu-a: 2-CU1 = 2: 5: 15 ( Fig. 44 ); length of hind wing 4.15 × its width (112: 27); 1-M: 1r-m: 2-SC+R = 4: 7: 7 ( Fig. 45 ).

Legs. Length of hind femur, tibia and basitarsus, 6.0, 13.0 and 12.0 × as long as their width, respectively; hind tarsus 0.4 × hind tibia (24: 65); hind basitarsus 0.8 × second-fifth tarsus (24: 30); fourth hind tarsus 0.7 × fifth tarsus without pretarsus (5: 7).

Metasoma. First metasomal slightly narrowed behind spiracle; length of first tergite 2.3 × its apical width (34: 15); apical width of first tergite 3.75 × its minimum width (15: 4); first tergite depressed subapically, smooth basally and medially, striate laterally ( Fig. 42 ); ovipositor sheath 0.2 × fore wing (22: 114), and 0.65 × first tergite (22: 34); ovipositor sinuate.

Colour. Body yellow, except metasoma, first metasomal tergite and ovipositor sheath brown; eyes silver-grey; wing veins pale yellow, except vein r and pterostigma ventrally brownish-yellow; wing membrane hyaline.

Male. Unknown.

Host: Unknown.

Etymology. Named after type locality, Tuyen Quang Province, Northeast Vietnam.

Distribution. Vietnam: Tuyen Quang (Na Hang).

Figures

FIGURE 34. Streblocera (Eutanycerus) tuyenquangnensis Long, sp. n. Holotype, female. Habitus, lateral view

FIGURES 35–45. Streblocera (Eutanycerus) tuyenquangnensis Long, sp. n. Holotype, female. 35 Head, dorsal view 36 Head, frontal view 37 Head, lateral view 38 Mesonotum 39 Mesopleuron 40 First-seventh flagellomeres, lateral view 41 Scapus 42 First metasomal tergite 43 Propodeum 44 Fore wing 45 Hind wing.