Ypsiloncyphon bicolor, Yoshitomi, Hiroyuki, 2015

Yoshitomi, Hiroyuki, 2015, New species of the genus Ypsiloncyphon (Insecta: Coleoptera: Scirtidae: Scirtinae), Zootaxa 3904 (4), pp. 451-500 : 473-474

Ypsiloncyphon bicolor sp. n.

( Figs. 13 E, 13F, 18, 19)

Type material. Holotype ( NMW): male, “S-VIETNAM Nam Cat Tien Nat. Park 1. -15. 5. 1994 Pacholatko & Dembicky”, genit. s. no. HY 933. Paratypes ( NMW, EUMJ, NSMT): 14 males & 17 females, same data as for the holotype; 2 males & 1 female, “NW-THAIL.: Chiang Mai 98 º57’E 18º49’N, Zoo 1. -8. 5. 1989, Malicky & Chantaramongkol LF”; 1 female, “N-THAILAND, 10. -17. 4. 18 º49’N 98º57’E Chiang Mai, Zoo (Licht) leg. Chantaramongkol & Malicky 1989”; 1 male, “N-THAILAND, 1. -8. 6, 18 º49’N 98º57’E Chiang Mai, Zoo (Licht) leg. Chantaramongkol & Malicky 1989”, genit. s. no. HY 844.

Description. Male. Body ( Fig. 13 E) oval, well convex dorsally, shiny, closely covered with silver setae. Coloration of head, antennae, pronotum and legs yellowish orange; scutellar shield, elytra, meso- and metaventrites and abdomen black.

Head relatively large, flat dorsally, finely punctate, front margin of clypeus shallowly concave. Eyes large, prominent; the distance between eyes about 1.8 times as long as the maximum diameter of an eye. Pronotum punctate as on head, depressed in lateral parts; anterior and lateral margins straight; posterior margin gently arcuate; antero- and postero-lateral corners obtuse; PW/PL 1.97–2.27 (2.10). Scutellar shield moderate in size, punctate as on head, equilaterally triangular. Elytra ovate, widest at the middle, densely punctate, strongly convex dorsally in caudal 2/5; humeral parts projecting dorso-anteriorly; apices right-angled; EL/EW 1.19–1.29 (1.24); EL/PL 3.89–4.33 (4.06); EW/PW 1.53–1.60 (1.56); TL/EW 1.47–1.62 (1.54).

Sternite III ( Fig. 18 A) glabrous in lateral parts. Caudal margin of sternite VII ( Fig. 18 A) gently arcuate. Tergite VII lacking apodeme, lightly projecting in apical margin; tergite VIII ( Fig. 18 B) lightly sclerotized, trapezoidal, bearing long setae and minute spines along apical margin, with a pair of slender apodemes; tergite IX ( Fig. 18 C) lightly sclerotized, trapezoidal, apical margin convex, apical part sparsely punctate, with a pair of long and slender apodemes; sternite VIII small; sternite IX ( Fig. 18 D) moderately sclerotized, very long, U-shaped, covered with transverse keels in apical part, pointed at apices. Tegmen ( Fig. 18 E) moderately sclerotized, Y-shaped, as long as sternite IX; apical 1/3 (parameres) bifid, bearing minute spines in apical parts. Penis ( Fig. 18 F) short, moderately sclerotized, about 0.75 times as long as tegmen; pala relatively long, expanded in basal part; parameroids long and wide, sparsely punctate in lateral parts, obtuse at apex; trigonium long and slender, as long as parameroids, rounded at apex.

Female ( Fig. 13 F). Sexual dimorphism distinct in the presence of U-shaped depressed excitator situated around basal 2/5 of elytral sutures; PW/PL 2.03–2.32 (2.18); EL/EW 1.18–1.36 (1.30); EL/PL 3.78–4.64 (4.24); EW/PW 1.39–1.62 (1.50); TL/EW 1.47–1.68 (1.60). Caudal margin of sternite VII ( Fig. 19 A) arcuate. Tergite VIII ( Fig. 19 B) moderately sclerotized, trapezoidal, bearing short spines on caudal margin, with a pair of long and slender apodemes protruding from antero-lateral corners. Sternite VIII ( Fig. 19 C) moderately sclerotized, oblong, with a long median apodeme. Ovipositor ( Fig. 19 D) long, with a branch in apical 8/9 of baculus; approximate ratio of stylus, coxite and baculus (n = 1) as 1.0: 5.0: 31.7; sclerotized structures absent.

Measurements. Male (n = 4): TL 1.72–1.86 (1.77) mm; PW 0.70–0.75 (0.73) mm; PL 0.33–0.38 (0.35) mm; EW 1.10–1.20 (1.15) mm; EL 1.38–1.48 (1.42) mm. Female (n = 9): TL 1.58–1.88 (1.77) mm; PW 0.65–0.80 (0.74) mm; PL 0.28–0.38 (0.34) mm; EW 0.97–1.15 (1.10) mm; EL 1.25–1.53 (1.43) mm.

Distribution. Thailand, Vietnam.

Remarks. This is a remarkable species in having a distinctive penis in which the trigonium is long and slender and the parameroids are wide.

Etymology. The species name refers to the bicolored body, i.e., yellowish head and pronotum and black elytra.

Figures

FIGURE 13. Habitus of Ypsiloncyphon spp., holotype, male (except for F). A) Y. guamensis sp. n., B) Y. philippinensis sp. n., C) Y. panayensis sp. n., D) Y. chlorizanoides sp. n., E) Y. bicolor sp. n., F) Y. bicolor sp. n., paratype, female, G) Y. sumatranus sp. n., H) Y. acer sp. n., I) Y. nokrekensis sp. n., J) Y. boukali sp. n., K) Y. javanicus sp. n., L) Y. nepalensis sp. n. Scales: 1.0 mm.

FIGURE 18. Ypsiloncyphon bicolor sp. n., holotype, male. A) abdominal sternites III – VII, B) tergite VIII, C) tergite IX, D) sternite IX, E) tegmen, F) penis in ventral view.

FIGURE 19. Ypsiloncyphon bicolor sp. n., paratype, female. A) sternites V – VII, B) tergite VIII, C) sternite VIII, D) ovipositor.