Gergithus tristriatus, sp. nov.

(Figs. 19–38, 40, 42)

Description: Male length (N=2) (including tegmen): 5.0–5.1 mm, length of tegmen: 4.5–4.6mm; female length (N=3) (including tegmen): 5.6–5.8 mm, length of tegmen: 5.0–5.2mm.

Colouration: General colour pale yellow (one male specimen pale greenish yellow). Vertex pale yellow. Eyes dark brown. Frons dark brown with yellowish green fascia near clypeus (Fig. 22). Frontoclypeal suture black. Clypeus fusco-piceous. Rostrum yellow brown. Antenna brown. Pronotum pale yellow and suffused with black near posterior margin medially. Mesonotum pallid greenish yellow with or without a blackish stripe medially. Tegmen translucent, pale yellow at base, with four marks: two wide oblique black stripes at basal third and apical third, one short, narrow, oblique stripe at middle of post marginal portion, one black spot at apical third of tegmen (Figs. 21, 23). Wing light brown, veins hazel with dark microtrichia (Fig. 24). Legs yellow brown, apices of teeth of hind legs black.

Head and thorax: Vertex wide, anterior margin straight, posterior margin slightly concave, 3.3 times wider than long in midline, disc distinctly depressed (Figs. 19, 20). Frons broad with numerous punctures, 1.4 times wider at widest part than at base, lateral margin distinctly elevated (Fig. 22). Frontoclypeal suture approximately straight. Clypeus relatively small, slightly depressed at basal third, disc prominent. Rostrum attaining post-trochanters. Pronotum anterior margin produced between eyes, posterior margin straight medially, disc slightly concave with minute punctures. Mesonotum triangular and wrinkled, 2.1 times wider at widest part than long (Fig. 20). Tegmen 1.6 times longer than widest part (Figs. 21, 23). Wing with veins lightly reticulate, veins with minute setae, 0.7 times length of tegmen, 2.3 times longer than widest part (Fig. 24). Spinal formula of hind leg 3 7–14 –2, Ƥ 9–16–2.

Male genitalia: Anal tube nearly triangle in dorsal view and narrow at base, widest at apical part, apical margin convex at middle, with one angulate prominence on each side, and middle part concave (Fig. 25). Anal column narrow and short (about 0.1 times as long as anal tube). Suspensorium narrow, with faintly pigmented median field. Pygofer with dorsolateral angles not developed, posterior margin obtusely projecting medially, anterior margin shallowly concave in upper half (Fig. 38). Connective slightly thick (Figs. 26, 36). Aedeagus shallowly U-shaped in lateral view, with asymmetrical process on each side of base, left process uncinate and dumpy, apex acuminate and directed caudad, right process elongate and comparatively straight, apex directed cephalad (Figs. 26, 36, 37). Phallobase with dorso-lateral and ventral lobes. Each dorso-lateral lobe of phallobase with apical spinous process. Ventral phallobase lobe acuminate at apex, longer than dorsolateral phallobase lobes, and strongly sclerotized. Genital style small, with concave posterior margin, caudo-ventral angle rounded (Fig. 38). Capitulum of style, in dorsal view, with two obtuse apical processes, and large lateral tooth with apex divided into two spinules directed ventrally, a tuberculiform process under lateral teeth (Fig. 30).

Female genitalia: Sternum VII with posterior margin clearly concave in middle (Figs. 35, 40). Anal tube nearly ovate in dorsal view, base wider than apex (Fig. 27), apical margin incised (Fig. 40). Anal column wide (about 0.3 times as long as anal tube). Gonoplac slightly prominent medially, border between first and second gonoplac lobes obsolete, third gonoplac lobes membranous and fork strongly sclerotized (Figs. 32, 34). Proximal part of posterior connective lamina of gonapophyses IX convex in lateral view, median field with bivalvate apical part, lateral fields not projecting (Figs. 29, 31). Gonocoxa VIII nearly rectangular, ventral margin slightly concave. Endogonocoxal process gradually narrowed to apex. Anterior connective lamina of gonapophysis VIII bearing three teeth in apical group and two teeth with carinae in lateral group (Figs. 28, 33).

Female reproductive organs: Bursa copulatrix well developed with shrinking ductus at basal half and large pouch at apical half. Posterior vagina thick, with small horseshoe-like sclerotized plate near base of bursa copulatrix ductus. Anterior vagina long and relatively thin. Oviductus communis thin and short. Spermatheca well-developed, ductus receptaculi relatively long, with elongate pouch proximally and elongated thin ductus preapically, diverticulum receptaculi distinctly dilated or bulbous with wider apical part than basal part, spermathecal pump comparatively short and acuminate with compact helix-shaped loop (Fig. 42).

Material examined: Holotype: male, Wangxiangtai, Yuanjiang County, Yunnan Province, China, 18 July 2006, coll. Xueqin Shi. Paratypes: 1 female, same data as holotype; 1 male, 2 females, Daxing Country, Mili Town, Yuanjiang County, Yunnan Province, China, 22 July 2006, coll. Zhonghua Fan.

Remarks: This new species resembles G. bistriatus (Schumacher), 1915 from which it can be distinguished by the three black oblique stripes on tegmen and one black spot at apical third of tegmen, whereas in G. bistriatus, the tegmen has two transverse brown bands medially and on apical third, always interrupted, and with a brown spot at apex. The two species also differ in male genitalia.

Etymology: The specific epithet refers to the three stripes on the tegmen.