Ypsiloncyphon laosensis, Yoshitomi, Hiroyuki, 2015

Yoshitomi, Hiroyuki, 2015, New species of the genus Ypsiloncyphon (Insecta: Coleoptera: Scirtidae: Scirtinae), Zootaxa 3904 (4), pp. 451-500 : 453-454

Ypsiloncyphon laosensis sp. n.

( Figs. 1 A, 2)

Type material. Holotype ( EUMJ): male, “Ph. Pan (Mt.) Houaphan Prov. LAOS 28. IV. – 6. V. 2002 H. Yoshitomi leg.”

Description. Male. Body ( Fig. 1 A) oblong-oval, convex dorsally, shining, closely covered with yellowishwhite setae throughout. Coloration of body almost black, but anterior part of head, mouthparts, antennae and legs are pale brown.

Head moderate in size, slightly convex dorsally, granulate, with straight front margin of clypeus. Eyes moderate in size, prominent; the distance between eyes about 2.3 times as long as the maximum diameter of an eye. Pronotum granulate as on head; front margin straight in dorsal aspect; lateral margins gently arcuate; antero-lateral corners rectangular, slightly produced anteriorly; postero-lateral corners obtuse; PW/PL 1.88. Scutellar shield subtriangular, finely punctate. Elytra oblong-oval, subparallel-sided near base to apical 1/3, finely and densely punctate; apices rectangular; EL/EW 1.51; EL/PL 4.08; EW/PW 1.44; TL/EW 1.88.

Caudal margin of sternite VII ( Fig. 2 A) gently arcuate. Tergite VIII ( Fig. 2 B) well sclerotized, H-like in shape; posterior part curved inward, pointed at apices, sparsely covered with short setae. Tergite IX ( Fig. 2 C) well sclerotized, consisting of two hemitergites, each as long as tergite VIII, rod-like, bilobed in apical 1/4. Tegmen ( Fig. 2 D) long, well sclerotized, Y-shaped, bilobed in apical 3/7, with pointed apices. Penis ( Fig. 2 E, F) as long as tegmen, well sclerotized; parameroids gently tapered apically from apical 1/5, curved dorsally, closely covered with fine punctures and spines, obtuse at apex; pala expanded laterally; trigonium prolonged ventrally, with two pairs of denticles on lateral margin of proximal part.

Female. Unknown.

Measurements. Male. (n = 1): TL 2.03 mm; PW 0.75 mm; PL 0.40 mm; EW 1.08 mm; EL 1.63 mm.

Distribution. Laos.

Remarks. This species is remarkable in having a uniquely shaped tergite VIII, tergite IX (consisting of a pair of hemitergites), and penis (armed with spines in apical part).

Etymology. The species is named after the type locality.

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 2. Ypsiloncyphon laosensis sp. n., holotype, male. A) abdominal sternites III – VII, B) tergite VIII, C) tergite IX, D) tegmen, E) penis in ventral view, F) penis in lateral view.