Ypsiloncyphon acer Yoshitomi, 2015, sp. n.
Creators: name: Yoshitomi, Hiroyuki
Publisher: name: Zenodo
Year: 2015
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Scirtidae
Ypsiloncyphon
Ypsiloncyphon acer

description: Ypsiloncyphon acer sp. n.
(Figs. 13 H, 21)
Type material. Holotype (EUMJ): male, “[North Thai] Maeo Khun Klang 1350 m, Doi Inthanon 21. X. 1983 M. Sakai”. Paratypes (NSMT, NMW, EUMJ): 3 males, same data as for the holotype, s. no. HY 818; 1 male, same locality and collector, but 20. X. 1983; 1 male, “ THAILAND) Maeo Khun Klang, 1300 m Doi Inthanon 21. X. 1983 M. Tomokuni”.
Description. Male. Body (Fig. 13 H) oval, convex dorsally, shining, closely covered with yellowish-white setae throughout. Coloration of body blackish-brown, but mouthparts, antennae and legs yellowish-brown; pronotum reddish-brown.
Head moderate in size, slightly convex dorsally, granulate, with straight front margin. Eyes moderate in size, prominent; the distance between eyes about 1.6 times as long as the maximum diameter of an eye. Antennae (Fig. 21 A) short and stout; approximate ratio of each antennal segment (n = 1) as 5.0: 3.0: 1.0: 5.5: 5.6: 6.2: 6.2: 6.2: 6.5: 6.0: 9.0. Pronotum granulate as on head; front and lateral margins almost straight; antero-lateral corners about 120º, lightly produced anteriorly; postero-lateral corners about 120º; posterior margin bisinuous; PW/PL 2.23–2.56 (2.40). Scutellar shield small, sparsely punctate, equilaterally triangular. Elytra oval, widest in middle, closely covered with fine punctures; apices rectangular; humeral parts weakly projecting; EL/EW 1.25–1.36 (1.30); EL/PL 4.51–5.31 (4.81); EW/PW 1.52–1.56 (1.54); TL/EW 1.54–1.62 (1.58).
Caudal margin of sternite VII (Fig. 21 B) arcuate. Tergite VIII (Fig. 21 C) moderately sclerotized, trapezoidal, bearing long setae and short spines in apical part, with a pair of long apodemes; sternite VIII (Fig. 21 E) moderately sclerotized, long rod-like shaped, expanded in apical part; tergite IX (Fig. 21 D) moderately sclerotized, inversely U-shaped, sternite IX (Fig. 21 F) moderately sclerotized, U-shaped, very long, pointed at apices. Tegmen (Fig. 21 G) very long, moderately sclerotized, Y-shaped, bifid in apical 1/2; parameres very long, bearing short spines in apical part, with rounded apices. Penis (Fig. 21 H) long, moderately sclerotized, about 0.7 times as long as tegmen; parameroids obtuse at apex, finely punctate; pala gently tapered in proximal 1/3; trigonium projecting from proximal 2/3 to 5/6, covered with small spines in apical part.
Female. Unknown.
Measurements. Male (n = 4): TL 1.93–2.02 (1.96) mm; PW 0.78–0.83 (0.81) mm; PL 0.32–0.35 (0.34) mm; EW 1.20–1.27 (1.24) mm; EL 1.58–1.70 (1.62) mm.
Distribution. Thailand.
Remarks. This species is closely related to Ypsiloncyphon formosus (Klausnitzer) in the characteristics of the male genitalia, and differs from it in the long parameres which bear short spines and a slender penis.
Etymology. The species name refers to the pointed sternite IX.
description: Published as part of Yoshitomi, Hiroyuki, 2015, New species of the genus Ypsiloncyphon (Insecta: Coleoptera: Scirtidae: Scirtinae), pp. 451-500 in Zootaxa 3904 (4) on pages 476-477, DOI: 10.11646/zootaxa.3904.4.1, http://zenodo.org/record/239899