Female. Internal organ of reproductive system (Fig. 5c). Vagina elongate, with median oviduct situated at ventro-apical part, vagina abruptly narrowed in apical part and extended into a short tube from where diverticulum and spermathecal duct are arising; diverticulum short, 0.1 times as long as adult body length, evenly thinned apically, slender tube-shaped and spiral; spermathecal duct 0.3 times as long as diverticulum; spermatheca slender tube-shaped and spiral, thinner than spermathecal duct and 0.7 times longer than diverticulum, with basal part extended into a short tube, at opening of accessory gland. Accessory gland thin in basal part and the remainder relatively thick, 1.8 times as long as spermatheca.
Description. Male (Fig. 6). Head black, light brown on middle line of vertex, mouthparts light yellow, more or less darkened at maxillary and labial palpi, dark brown at apices of mandibles, antennae black, light yellow at apex of each antennomere, pronotum light yellow, with a large dark brown marking on disc, scutellum light yellow, elytra light yellow and mottled with irregular black brown markings, legs light yellow, black at bases of coxae and tibiae and apices of femora and tarsomeres, more or less darkened at outer sides of femora and outer and dorsal sides of tibiae, prosternum light yellow, meso- and metasterna and abdominal ventrites dark brown, light yellow at posterior margin of abdominal ventrites and the whole terminal ventrite. Body densely covered with light brown pubescence, mixed with slightly long, semirecumbent light brown pubescence and erect black brown setae on elytra. Head subquadrate, temples straight and slightly converging posteriorly, dorsum moderately convex in central part, surface semilustrous, densely and finely punctate, each side with a smooth and rectangular impression behind antennal socket; eyes strongly protruding, head width across eyes distinctly narrower than pronotum; terminal maxillary palpomeres long-triangular, widest at basal one-third, with apical parts of inner margins arcuate and sharp, acute at apices; antennae extending to basal two-thirds length of elytra, antennomeres II about twice longer than wide at apices, III slightly longer than II, IV longest, from V to XI gradually shortened, XI pointed at apex. Pronotum about 1.25 times as wide as long, widest nearly in middle, anterior margin together with anterior angles and lateral margins rounded, posterior margin arcuate and narrowly bordered, posterior angles moderately sharp, protruding, disc distinctly convex on posterolateral parts, surface lustrous, finely and sparsely punctate. Elytral length about 4 times length of pronotum, 3 times as long as humeral width, with lateral margins slightly diverging posteriorly, surface semilustrous, rugulose-lacunose and finely punctate. Aedeagus (Figs. 33 ‒ 35): ventral process of each paramere bent ventrally about 60 degrees, with the bent portion at apical part distinctly longer than the basal portion, not thickened terminally, circular at apex in lateral view, dorsal plate distinctly shorter than ventral process, abruptly narrowed apically, acute at apex (Fig. 33 a); laterophyse hooked at apex. Female. Similar to male, but head slightly convex on dorsum, antennae shorter and extending to elytral midlength, pronotum moderately convex on posterolateral parts of disc, elytra with lateral margins distinctly diverging posteriorly, abdominal sternite VIII (Fig. 18) abruptly narrowed posteriorly, nearly flat on middle sclerotized part, with lateral margins strongly sclerotized at anterior part and nearly membranous at posterior part, posterior margin triangularly emarginated in middle, lateroapical angles subrectangular, anterior margin triangularly emarginated in middle, the lobe slightly sclerotized and triangular, sternite VII triangularly protuberant in middle of posterior margin. Body length: 7.5 ‒ 9.0 mm; width: 1.5 ‒ 2.0 mm.
Diagnosis. This species can be easily distinguished from others by the abdominal sternite VII of female triangularly protuberant in middle of posterior margin; aedeagus: ventral process of each paramere not thickened terminally, laterophyse hooked at apex.
Distribution. China (Xizang).
Etymology. This specific name is derived from the Latin septimus (seventh), referring to its characteristic abdominal sternite VII of female, which is triangularly protuberant in middle of posterior margin.
Type material. Holotype ♂ (MHBU): CHINA: Xizang: Mêdog, Hanmi, 2380 m, 9. VIII. 2003, leg. G. D. Ren. Paratypes: 22 ♂♂, 10 ♀♀ (MHBU): same data as holotype; 6 ♂♂, 4 ♀♀ (MHBU): same locality, 28. VII. 2013, leg. X. L. Bai & J. S. Shan. [all transliterated from Chinese labels].