Trechnites brevivalvus Zu and Li, 2016

Zu, Guohao, Li, Chengde, O, Published & V, Final, 2016, Two new species of Trechnites (Hymenoptera: Encyrtidae) from China and a key to Chinese species, Turkish Journal of Zoology 40 (1), pp. 35-39 : 36

3.1. Trechnites brevivalvus Zu and Li , sp. nov. ( Figure 1 )

Type material: Holotype. ♀ (E1304–01), CHINA, Yunnan Province, Longchuan County, 26– 28.04.2013, YPT. 1 ♀, leg. Guo-Hao Zu, Hui-Lin Han, Xiang-Xiang Jin, Chao Zhang ( NEFU).

Description. Female (holotype). Body length 1.36 mm. Body generally dark brown. Antennae with radicle brown, middle part of scape and basal part of pedicel yellowish brown, rest of antennae pale yellow to yellow. Eyes reddish brown. Ocelli red. Frontovertex and mesoscutum with green reflection; gena and scrobe with purple blue reflection; scutellum with bright golden green metallic reflection. Wings hyaline, the veins yellowish brown. Gaster brown, paler than thorax and sutures yellow. Legs yellow.

Head ( Figure 1A ) in facial view, 1.14× as wide as high, 2.92× as wide as frontovertex. Frontovertex with sculpture shallow and inconspicuous. Ocelli forming an acute triangle. Eyes with medial margins greatly diverging ventrally. Antennal scrobes moderately deep, meeting dorsally, inverted V-shaped, sides more or less rounded, toruli separated from mouth margin by their own widths, their dorsal margins on the level with ventral eye margins. Malar space 0.53× as long as eye length.

Antenna ( Figure 1C ) with radicle 3.38× as long as wide; scape cylindrical, about 6.16× as long as wide; pedicel about 2.21× as long as wide, shorter than F1–F3 combined; F1 1.09× as long as wide; F2 1.08× as long as wide; F3 1.1× as long as wide; F4 and F5 as long as wide; clava 3-segmented, 2.38× as long as wide and shorter than F3–F5 combined, apex strongly obliquely truncate, truncate part nearly two thirds of the clava; funicle with linear sensillae on F3–F5.

Thorax ( Figure 1B ). Mesoscutum 2.47× as wide as long, with notaular lines complete, more or less reaching its posterior margin. Scutellum 1.04× as wide as long, and 1.53× as long as mesoscutum, apex acute, reaching posterior margin of metanotum. Mesoscutum with fine, scale-like, more or less transverse sculpture; scutellum with coarse, polygonal sculpture, and more or less longitudinally elongate laterally.

Forewing ( Figure 1D ) 2.4× as long as wide; costal cell broad, 8.15× as long as wide, with 1–2 complete lines of setae along anterior margin and 2 incomplete on about basal half; venation less than half (0.44×) the length of forewing; marginal vein punctiform, postmarginal vein very short, but distinct, stigmal vein long and straight, truncated and enlarged apically. Linea calva nearly closed by 1–2 lines of setae posteriorly, uninterrupted, filum spinosum directed to distal part of stigmal vein. Basal cell with a naked area near base; also a small naked area just on the above the base of stigmal vein. Marginal fringe short, shorter than the setae on basal cell.

Hind wing ( Figure 1E ) relatively wide, 3.67× as long as wide; submarginal vein distinctly down curved. Linea calva present, open posteriorly, uninterrupted. Basal cell naked on posterior one-third; marginal fringe remarkably much longer than the setae on basal cell.

Legs ( Figure 1F ). Forelegs and hind legs unmodified. Apical rim of mid tibia with 7 pegs; mid tibial spur considerably stout and robust, about 0.88× as long as corresponding basitarsus, with apex narrowly rounded; mid tarsi thicker than foretarsi and hind tarsi.

Gaster ( Figure 1B ) 1.49× as long as thorax. T1–T3 distinctly sculptured on posterior half submedially. Cercal plates situated slightly distal to middle of gaster. Ovipositor short, 0.64× as long as mid tibia, gonostylus free, 2× as long as wide and 0.38× as long as second valvifer.

Relative measurements (length/width): thorax 495; gaster 738; OL 228. MS 137; FV 144, EL 257, POL 89, OOL 4, OCL 22. Antenna: radicle 65/19; scape 185/30; pedicel 74/34; F1 29/26; F2 34/31; F3 41/37; F4 43/43; F5 46/46; clava 127. Forewing 1171/488. Hind wing 653/178.

Male. Unknown.

Host. Unknown.

Etymology. The specific name refers to the short ovipositor and third valvula.

Comparative notes. Trechnites brevivalvus is most closely related to T. angolensis (Afrotropical Region), T. versicolor (Afrotropical Region), and T.flavipes (Palaearctic Region) having 3-segmented clava, complete notaular lines, and yellow legs, but can be distinguished from T. angolensis and T. versicolor by strongly obliquely truncate clava apically (more or less rounded in T. angolensis and T. versicolor ), and the coloration of antennae; from T. flavipes by having ovipositor 0.64× as long as mid tibia (1.18× in T. flavipes ), linea calva nearly closed (completely open in T. flavipes ), scape more than 6× as long as wide (5× in T. flavipes ), and gonostylus about 2× as long as wide (5.5× in T. flavipes ).

Figures

Figure 1. (A–F) T. brevivalvus sp. nov. (female): A) Frontal aspect of head, B) Dorsal aspect of thorax and gaster, C) Antenna, D) Forewing, E) Hind wing, F) Legs. Scale bars = 100 μm.