Eustrangalis (Eustrangalis) fuscisuturalis sp. nov. ḃDz真AEħ牛
( Figs 2a, b View FIGURE 2 , 3a View FIGURE 3 , 4 View FIGURE 4 , 5a, c View FIGURE 5 )
Description. Male. Body length 14.0–16.0 mm, humeral width 3.0– 3.5 mm. Body mostly yellowish-brown, with blackish-brown to black stripes and recumbent short yellowish-brown setae. Head mostly dull yellowish-brown, clothed with some yellowish-brown hairs on vertex; apex of labrum and half apex of mandibles blackish-brown; occiput with a broad black stripe that extends narrowly forwards along the margins of each upper eye lobe to the vertex, sometimes not extending forwards ( Fig. 4c, d View FIGURE 4 ); vertex and occiput sometimes mostly blackish-brown ( Fig. 4e, f View FIGURE 4 ). Antennae yellowish-brown, slightly lighter towards apex. Pronotum mostly yellowish-brown, clothed with a recumbent yellowish-brown seta in each punctation and provided with a conspicuous longitudinal black stripe on each side, the black stripe sometimes occupying the most of pronotum ( Fig. 4e, f View FIGURE 4 ). Elytra slightly lighter in colour than head and pronotum; each elytron with a distinct blackish-brown longitudinal stripe from humeri extending backwards to apex, sometimes the strip gradually light chestnut in colour from behind the shoulder backwards to the apex ( Fig. 4a–f View FIGURE 4 ); the suture entirely blackish-brown to chestnut, epipleuron behind basal fourth blackish-brown to chestnut; each punctation bears a recumbent short yellowish-brown seta. Abdominal ventral surface darker than that of head and thorax. Setae on ventral surface of meso- and metathorax denser and longer than those on abdominal ventral surface.
Head densely punctate, more sparsely and coarsely on clypeus, with a smooth, impunctate, subsemicircular region on the middle of the apical frons. Antennae slightly exceeding elytral apices; scape distinctly curved and thickened towards apex in lateral view, slightly shorter than antennomere III; antennomere V longest; relative lengths from antennomeres I to XI as follows: 27: 5: 28: 25: 34: 30: 29: 26: 25: 24: 26.
Pronotum densely punctate, slightly longer than basal width, deeply constricted at apical fifth and moderately so at basal fourth; disc convex above and roundly prominent laterally, with a smooth, glabrous, narrow central region; base distinctly bisinuate. Elytra about 3.1 times as long as humeral width, straightly convergent from humeri towards apex; disc longitudinally depressed along suture, with deep punctures which are coarser and sparser than those of head and pronotum, and becoming shallower towards apex; apex obliquely emarginate, with sharply toothed outer angle and pointed inner angle.
Metaventrite thick, strongly convex beneath, finely punctate and provided with a pair of longitudinally ridged small projections beside median line at posterior half. Abdomen sparsely and finely punctate; apical region of fifth ventrite triangularly depressed on centre, with slightly emarginate apical margin. Legs short and slender; metatibia inwardly thickened from about apical two-fifths; metatarsus with first tarsomere about 1.7 times as long as the next two combined.
Male genitalia. Tergite VIII ( Fig. 5a View FIGURE 5 ) with both sides subparallel at basal half, then gradually curving towards apex; apex broadly rounded, clothed with short to medium straight setae on apical half except for a central glabrous triangular region. Tegmen yellowish brown, slightly bent in lateral view. Parameres ( Fig. 5c View FIGURE 5 ) relatively short, moderately separated each other and slightly curved inward near apices; each one length 2.1 times as long as width, lateral edge partly dark brown, apex blunt rounded with several long setae.
Female. Unknown.
Material examined. Holotype (male), China: Hubei province, Yichang (đš), Dalaoling National Nature Reserve (kŧ岭),Zhucaogou (Bdz沟), alt. 1560 m, 1 May 2014, coll. Guanglin Xie. Paratypes: two males, same data as for the holotype ; two males, China: Hubei province, Shengnongjia National Forest Park (ėƛ架),Yousongping (油松坪), 16 June 2022, coll. Weiwei Zhao ; one male, China: Shaanxi province, Yangxian (洋县), Huayang town (华DDz), Hongshiyao (Ḧ石±), 33°38′24″N, 107°29′24″E, alt. 1270 m, 12 May 2018, coll. Lanbin Xiang GoogleMaps ; one male, China: Shaanxi province, Meixian (眉县), Yingtou town (üíDz), Honghegu National Forest Park (Ḧ河ĕ), 34°5′11″N, 107°45′23″E, alt. 1100 m, 5 May 2019, coll. Heng Xin. The GoogleMaps holotype and paratypes are deposited in the Insect Collection,College of Agriculture, Yangtze University (YZU).
Distribution. China: Hubei, Shaanxi.
Etymology. The species name is a combination of the Latin word ‘fuscus’ and ‘sutura’, referring to the fuscous suture of the elytra.
Comments. The new species is similar to E. latericollis and E. distenioides . It differs from the former by the elytra with the distinct blackis-brown to chestnut longitudinal stripes from the humeri to apices, the suture and epipleuron blackish-brown to chestnut, the tergite VIII with more broadly rounded apex, parameres shorter (length/ width ratio about 2.1), while in E. latericollis , the elytra are black only on humeri, the suture is blackish-brown to black only a short distance after scutellum, the length/width ratio of the paramere is about 3.2. It is different from the latter by the antennae yellowish-brown, the pronotum with the black stripe extending to the base and apex and the abdomen entirely dull yellowish-brown.
The new species was captured on the flowers of Litsea ichangensis Gamble and Cornus alba Linnaeus , two of the currently known plants whose flowers are visited.
