Eurystylus yixuanae n. sp.

(Figs. 1A–B, 2 E−F, 5A−H, 10A−G, 14A−D)

Diagnosis: Recognized readily by its yellow-green basic coloration; wide, tumid body shape; uniformly pale head that lacks black, velvety macula on frons; and yellowish pronotum with a pair of dark ocellate spots. These unique characters enable this new species to be distinguished from any known congeners.

Description. Male: Body ovoid, boxlike, stout; general coloration yellow green, partly pale olive green (Fig. 1A–B); dorsum more or less shining, with uniformly distributed, sericeous, reclining setae and sparsely distributed, simple, semierect setae (Fig. 10B). Head pale olive green, shining, lacking fuscous, clustered micro-pilosity on frons; eye small; vertex wide. Antenna dark brown, partly tinged with red, generally thick; segment I pale olive brown, except for darkened apex; basal 2/3 of segment II pale reddish brown; extreme bases of segments III and IV pale. Labium pale reddish brown, reaching but not exceeding apex of mesocoxa; apical half of segment IV darkened. Pronotum shining, with a pair of dark, circular spots on disk and smoky brown posterior margin; mesoscutum reddish brown; scutellum yellowish brown, usually widely brownish medially; thoracic pleura yellowish brown; scent efferent system as in Fig.10C. Hemelytron dark brown, strongly declivous at cuneal fracture; exocorium (embolium) and basal half of cuneus yellowish brown; membrane pale smoky brown, semitransparent, with dark brown veins. All coxae and legs yellowish brown; apical half of each tarsomere III darkened; pretarsal structure as in Fig. 10F. Abdomen uniformly yellowish brown. Male genitalia (Fig. 5A–C): Left paramere C-shaped, with inflated hypophysis (Fig. 5A); right paramere straight, with small hypophysis (Fig. 5B); vesica with four lobal-sclerites as in Fig. 5C (terminology of the sclerites sensu Yasunaga et al., 2017).

Female: Almost similar to male in overall appearance and biometrics; body slightly larger and stouter; scutellum not widely darkened, with three brown stripes (Fig. 1A). Female genitalia (Figs. 5D–H, 14A–D): sclerotized rings small, thick-rimmed, situated near lateral margins of genital chamber (Fig. 5D–F); posterior wall with small, rounded dorsal structure (Fig. 5H); interramal sclerite semi-circularly widened, densely covered with spinules (Fig. 14B–C).

Measurements. See Table 1.

Etymology. Named after Ms. Yi-Xuan Hsieh who kindly provided a specimen as well as some images of live individuals of this new species for this study; a noun in genitive case.

Distribution. Taiwan (Kaohsiung, Pingtung).

Biology. Unknown.

Type material. Holotype (♁), TAIWAN: Pingdung (Pingtung) Co., Siangjao Bay, 21°55'42.7''N, 120°49'40.2''E, UV lighting, Y.-C. Lan & Y.-H. Peng, 27 May 2011 (AMNH _ PBI 00380763) (NMNS) . Paratypes. TAIWAN: 1♁ 1♀, same data as for holotype (NMNS); 1♀, Kaohsiung, Mt. Zhongliao-shan, 22°49'48"N 120°25'57"E, 30 May 2013, Y. X. Hsieh (TYCN) .