Ypsiloncyphon guamensis, Yoshitomi, Hiroyuki, 2015

Yoshitomi, Hiroyuki, 2015, New species of the genus Ypsiloncyphon (Insecta: Coleoptera: Scirtidae: Scirtinae), Zootaxa 3904 (4), pp. 451-500 : 467

Ypsiloncyphon guamensis sp. n.

( Figs. 13 A, 14)

Type material. Holotype ( BPBM): male, “ GUAM: Mt. Lamlam 400 m Nov. 27. 1952 ”, “Pacific Soc. Pd. Micronesia Surv J. L. Gressitt”, genit. s. no. HY 929.

Description. Male. Body ( Fig. 13 A) oval, convex dorsally, shiny, closely covered with silver setae. Coloration of body dark brown, but anterior part of head, antennae, mouthparts and legs paler.

Head moderate in size, slightly convex dorsally, finely punctate, front margin of clypeus shallowly concave. Eyes large, prominent; the distance between eyes about 2.0 times as long as the maximum diameter of an eye. Pronotum punctate as on head, slightly depressed in lateral parts; anterior margin straight; lateral and posterior margins gently arcuate; antero- and postero-lateral corners obtuse; PW/PL 2.27. Scutellar shield moderate in size, punctate as on head, equilaterally triangular. Elytra oval, widest at the middle, densely punctate; humeral parts weakly projecting dorso-anteriorly; apices right-angled; EL/EW 1.20; EL/PL 3.94; EW/PW 1.44; TL/EW 1.51.

Caudal margin of sternite VII ( Fig. 14 A) gently arcuate. Tergite VIII trapezoidal, bearing short setae along apical margin, with long apodemes; tergite IX trapezoidal, with long apodemes; sternite VIII ( Fig. 14 B) T-shaped, short; sternite IX ( Fig. 14 C) moderately sclerotized, U-shaped, covered with transverse keels in apical 3/5, pointed at apices. Tegmen missing. Penis ( Fig. 14 D) moderately sclerotized, short; pala relatively long, expanded in basal part; parameroids relatively short, gently tapered posteriorly, obtuse at apex, sparsely punctate; trigonium short, situated in apical 1/3, projecting antero-ventrally.

Female. Unknown.

Measurements. Male (n = 1): TL 1.63 mm; PW 0.75 mm; PL 0.33 mm; EW 1.08 mm; EL 1.30 mm.

Distribution. Guam.

Remarks. This species is related to Ypsiloncyphon panayensis sp. n., but differs from it by the following characteristics: 1) sternite IX short, about 1.3 times as long as penis (about 2.0 in panayensis ), and 2) keels of sternite IX present on apical 1/2 (1/ 3 in panayensis ).

Etymology. The species is named after the type locality.

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 14. Ypsiloncyphon guamensis sp. n., holotype, male. A) sternites V – VII, B) sternite VIII, C) sternite IX, D) penis in ventral view.