Ypsiloncyphon nomurai, Yoshitomi, Hiroyuki, 2015

Yoshitomi, Hiroyuki, 2015, New species of the genus Ypsiloncyphon (Insecta: Coleoptera: Scirtidae: Scirtinae), Zootaxa 3904 (4), pp. 451-500 : 456-457

Ypsiloncyphon nomurai sp. n.

( Figs. 1 C, 4)

Type material. Holotype ( NSMT): male, “Deo O Quy Ho (1,670m) Lao Cai Prov. [N- VIETNAM] 22. V. 1998 S. Nomura leg.”, genit. s. no. HY 828.

Description. Male. Body ( Fig. 1 C) oblong-oval, slightly convex dorsally, shining, closely covered with yellowish-white setae throughout. Coloration of body blackish-brown; mouthparts, antennae and legs pale brown.

Head moderate in size, weakly convex dorsally, closely granulate, straight front margin of clypeus. Eyes moderate in size, prominent; the distance between eyes about 3.0 times as long as the maximum diameter of an eye. Pronotum granulate like head; front margin almost straight; lateral and posterior margins gently arcuate; anterolateral corners right-angled, projecting anteriorly; postero-lateral corners about 120º; PW/PL 2.43. Scutellar shield small, equilaterally triangular, closely covered with fine punctures. Elytra oblong, widest at the middle, densely punctate; each elytron furnished with three costae; humeral parts slightly projecting; apices right-angled; EL/EW 1.36; EL/PL 4.66; EW/PW 1.41; TL/EW 1.65.

Caudal margin of sternite VII ( Fig. 4 A) gently arcuate. Tergites VIII–IX ( Fig. 4 B, C) moderately sclerotized, each consisting of a pair of hemitergites, bilobed and somewhat expanded apically, covered with short setae on apices. Tegmen ( Fig. 4 D) short, moderately sclerotized; proximal part long; parameres short, ring-shaped, forming ring around penis, covered with minute spines. Penis ( Fig. 4 E) long, moderately sclerotized, about 1.6 times as long as tegmen; pala slender, expanded in proximal part; parameroids bilobed in apical 1/6, finely punctate; trigonium short, simple, projecting from proximal 3/5 to 4/5.

Female. Unknown.

Measurements. Male (n = 1): TL 1.98 mm; PW 0.85 mm; PL 0.35 mm; EW 1.20 mm; EL 1.63 mm.

Distribution. Vietnam.

Remarks. This is a remarkable species in having short and ring-shaped parameres of the tegmen and bilobed parameroids of penis. The character state of parameres forming a ring around penis is similar to those of Nyholmia (Yoshitomi 2005; Klausnitzer 2013).

Etymology. This species is named after Dr. Shûhei Nomura (NSMT), the collector of the holotype.

Figures

FIGURE 1. Habitus of Ypsiloncyphon spp., holotype, male (except for K). A) Y. laosensis sp. n., B) Y. myanmarnus sp. n., C) Y. nomurai sp. n., D) Y. bifurcatus sp. n., E) Y. bicornutus sp. n., F) Y. borneensis sp. n., G) Y. brachytrigonium sp. n., H) Y. garoensis sp. n., I) Y. kedahensis sp. n., J) Y. prolongatus sp. n., K) Y. mendosus (Klausnitzer, 1980), non-type specimen, male. Scales: 1.0 mm.

FIGURE 4. Ypsiloncyphon nomurai sp. n., holotype, male. A) sternites V – VII, B) tergite VIII, C) tergite IX, D) tegmen, E) penis in ventral view.