Ypsiloncyphon prolongatus, Yoshitomi, Hiroyuki, 2015

Yoshitomi, Hiroyuki, 2015, New species of the genus Ypsiloncyphon (Insecta: Coleoptera: Scirtidae: Scirtinae), Zootaxa 3904 (4), pp. 451-500 : 464-467

Ypsiloncyphon prolongatus sp. n.

( Figs. 1 J, 12)

Type material. Holotype ( NMW): male, “NW-THAIL.: Chiang Mai 98 º57’E 18º49’N, Zoo 1.- 8. 5. 1989, Malicky & Chantaramongkol LF”, genit. s. no. HY 834. Paratype: 1 male ( NMW), “ THAILAND, Mae Ping 24. – 25. 6. 1991 leg. Malicky (Licht)”.

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

Head large, slightly convex dorsally, minutely granulate; front margin of clypeus slightly concave. Eyes moderate in size, prominent; the distance between eyes about 3.0 times as long as the maximum diameter of an eye. Pronotum granulate as in head; front margin straight; lateral margins gently arcuate; antero-lateral corners rightangled, projecting anteriorly; postero-lateral corners about 120º; posterior margin bisinuous; PW/PL 2.14. Scutellar shield small, equilaterally triangular, closely covered with fine punctures. Elytra oblong, widest at the middle, lightly depressed dorsally in anterior part, densely punctate; humeral parts distinctly projecting; apices rightangled; EL/EW 1.32; EL/PL 4.14; EW/PW 1.47; TL/EW 1.64.

Tergite VII ( Fig. 12 B) well sclerotized, strongly transverse, posterior margin medially with long narrow projection between two deep U-shaped notches, with a pair of short apodemes; caudal margin of sternite VII ( Fig. 12 A) shallowly concave. Tergite VIII ( Fig. 12 C) moderately sclerotized, trapezoidal, caudal margin with truncate lateral and rounded paramedian lobes separated by a wide mesal and a pair of narrow V-shaped notches, with a pair of long and slender apodemes; tergite IX ( Fig. 12 D) almost membranous, with a pair of long apodemes. Tegmen ( Fig. 12 E) long, well sclerotized, Y-shaped, bifid in apical 2/7 (parameres), with pointed apices, projecting in antero-lateral corners of parameres. Penis ( Fig. 12 F) very long, moderately sclerotized, about 1.3 times as long as tegmen; pala subparallel, concave in basal margin; parameroids subparallel, but somewhat expanded in apical 1/3, bilobed in apical 2/9, closely covered with minute serrations and spines in mesal part which is membranous; trigonium long, projecting from basal 1/3, obtuse at apex.

Female unknown.

Measurements. Male (n = 1): TL 1.80 mm; PW 0.75 mm; PL 0.35 mm; EW 1.10 mm; EL 1.45 mm.

Distribution. Thailand.

Remarks. This is a remarkable species in having the following characters: 1) caudal margin of tergite VII prolonged, 2) antero-lateral corners of parameres projecting, and 3) apical part of penis membranous and covered with minute serrations and spines.

Etymology. The species name refers to the extended mesal process on tergite VII.

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