Spathius rectangulus, Tang & Belokobylskij & Chen, 2015

Tang, Pu, Belokobylskij, Sergey & Chen, Xue-Xin, 2015, Spathius Nees, 1818 (Hymenoptera: Braconidae, Doryctinae) from China with a key to species, Zootaxa 3960 (1), pp. 1-132 : 99-101

Spathius rectangulus sp. nov.

( Fig. 36 )

Description. Female. Body length 6.0 mm; fore wing length 4.5 mm.

Head. Antennae slender, weakly setiform, more than 47-segmented (apical segments missing). Scape 1.5 × as long as its maximum width. First flagellar segment 3.8 × as long as its apical width, 1.2 × as long as second segment. Head not depressed, its width (dorsal view) 1.4 × median length. Head behind eyes weakly convex in anterior half, roundly narrowed in posterior half. Transverse diameter of eye 2.1 × length of temple. Ocelli arranged in triangle with base 1.3 × as long as its sides; POL: Od: OOL = 7: 7: 23. Vertex very coarsely rugose-striate. Frons densely coarsely rugose-striate. Eye glabrous, 1.3 × as high as broad. Malar space 0.4 × eye height and 0.8 × basal width of mandible. Temple coarsely vertically striate, widely medially smooth or almost smooth. Face densely coarsely rugose-striate; its width 1.1 × eye height and 1.2 × height of face and clypeus combined. Clypeal suture distinct. Occipital carina complete dorsally, not joined below with hypostomal carina being obliterated on short distance upper base of mandible.

Mesosoma. Length of mesosoma 2.0 × its height. Pronotal keel distinct, its posterior branch widely fused with posterior margin of pronotum. Mesoscutum highly and perpendicularly elevated above pronotum. Mesoscutum with sparse and semi-erect setae along notauli and laterally; densely irregularly rugose-striate and granulate, with two convergent posteriorly carinae and narrow rugosity between them in medioposterior half; median and lateral lobes of mesoscutum with wide areas covered only granulate sculpture. Notauli complete, wide, shallow, densely crenulate. Prescutellar depression shallow, with five carinae, 0.3 × as long as scutellum. Scutellum densely granulate, flat, with distinct lateral carinae. Mesopleuron distinctly rugose and granulate; coriaceous-granulate below precoxal sulcus. Subalar depression shallow, wide, transversely rugose-striate and granulate. Precoxal sulcus deep, narrow, straight, finely coriaceous-granulate, running along anterior 0.6 of lower part of mesopleuron. Propodeum without distinct tubercles, with areas distinctly delineated by carinae; basal carina as long as anterior fork of areola; basolateral areas entirely coriaceous-granulate, rugose in apical half; rest of propodeum sparsely rugose; areola large and wide, pentagonal; petiolate area short, widened distally, distinctly separated from areola.

Wings. Fore wing 3.5 × as long as wide. Vein r arising weakly before middle of pterostigma. 3-SR: r: SR1: 2- SR = 20: 7: 40: 18. Second submarginal cell not narrowed distally, its length 3.0 × maximum width, 1.2 × length of first subdiscal cell. Vein cu-a postfurcal. Vein m-cu postfurcal. Vein CU1a not interstitial, arising from anterior 0.3 of distal vein of subdiscal cell. Hind wing vein M+CU 0.7 × as long as vein 1-M. Vein m-cu distinctly antefurcal, weakly curved towards base of wing.

Legs. Hind coxa densely granulate and transversely striate dorsally, granulate laterally, with basoventral tooth and corner. Hind femur dorsally finely striate and coriaceous-granulate, only coriaceous-granulate laterally and ventrally, 2.8 × as long as wide. Hind tibia apically with six spines on outer margin. Dorsal surface of hind tibia with long, sparse and semi-erect setae, their length 1.5–1.8 × maximum width of tibia. Hind tarsus 0.8 × as long as hind tibia. Hind basitarsus 0.7 × as long as second-fifth segments combined. Second segment of hind tarsus 0.4 × as long as basitarsus, as long as fifth segment (without pretarsus).

Metasoma. Petiole (lateral view) straight ventrally, distinct arched in basal half dorsally, with spiracular tubercles in basal third; entirely finely rugose, sparsely striate laterally. Length of petiole 3.1 × its apical width (dorsal view), 1.7 × length of propodeum. Second-fifth tergites with separate laterotergites. Second suture absent. Median length of second and third tergites combined 1.6 × basal width of second tergite, 0.8 × their maximum width. Second-fourth tergites densely regularly striate, with short rugulosity between striae, smooth apically. fifth tergite densely regularly striate, with short rugulosity between striae basally, finely semi-circularly transversely aciculate apically. Ovipositor sheath 3.3 × as long as petiole, 1.3 × as long as metasoma, 2.0 × as long as mesosoma, 1.1 × as long as fore wing.

Colour. Body yellowish brown; mesosoma reddish brown, media lobe of mesoscutum yellowish brown. Metasoma reddish brown. Antenna brown basally, darken toward apex. Palpi pale yellow. Legs yellowish brown; fore and middle coxae and all trochanters pale yellow; hind coxa and femur reddish brown; hind tibia and tarsus pale reddish brown. Ovipositor sheath brown, almost black apically. Fore wing faintly infuscate, with distinct maculation. Pterostigma dark brown, pale in basal 0.3.

Variation. Body length 5.2–6.4 mm; fore wing length 4.1–4.6 mm. Transverse diameter of eye 2.0 × length of temple. Length of second submarginal cell 3.2 × its maximum width. Hind wing vein M+CU 0.6 × as long as vein 1-M. Length of petiole 3.2 × its apical width (dorsal view), 1.8 × length of propodeum. Median length of second and third tergites combined 1.4 × basal width of second tergite, 0.7 × as long as their maximum width. Ovipositor sheath 3.1 × as long as petiole, 1.2 × as long as metasoma, 1.8 × as long as mesosoma, as long as fore wing.

Male. Unknown.

Material examined. Holotype: female, China, Hainan Prov., Jianfengling , 6.VI.2007, Liu Jingxian, No. 200703783 ( ZJUH) . Paratypes: 1 female, China, Hainan Prov., Jianfengling, 5–7. VI .2007, Xiao Bin , No. 200806908 ( ZJUH) ; 1 female, Hainan Prov., Baisha Yinggeling , 18.XI.2006, Tan Jiangli, No. 200805253 ( ZJUH) ; 1 female, Hainan Prov., Jianfengling, 6. VI .2007, Liu Jingxian , No. 200703845 ( ZISP) ; 1 female, Guangdong Prov., Shixing Chebaling , 22–28.VII.2008, Hong Chundan, No. 200807857 ( ZJUH) .

Comparative diagnosis. This new species belongs to the S. striolatus Cameron species group. Spathius rectangulus sp. nov. is similar to S. hephaestus Nixon , but differs in having the scutellum densely granulate (finely or partly very finely granulate-coriaceous in S. hephaestus ), petiole distinctly widen apically and entirely coarsely striate (weakly widened apically and finely sculptured in S. hephaestus ), second and third tergites short with their combined length 1.6 × basal width of second tergite and 0.8 × their maximum width (long with their combined length 2.0 × basal width and 0.9 × maximum width in S. hephaestus ), ovipositor distinctly shorter than body (almost as long as body in S. hephaestus ), and fifth tergite strongly convex (weakly convex in S. hephaestus ).

Etymology. From “rectum” (Latin for “straight”) and “angulus” (Latin for “angular”), because its mesoscutum highly and perpendicularly elevated above pronotum.

Distribution. China (Hainan, Guangdong).

Figures

FIGURE 36. Spathius rectangulus sp. nov. A, habitus, lateral aspect; B, head, frontal aspect; C, head, dorsal aspect; D, petiole, lateral aspect; E, fore wing; F, mesoscutum, dorsal aspect; G, mesosoma, lateral aspect; H, metasoma, dorsal aspect. Scale bar 0.5 mm.