Ischnosoma schmidti Kocian & Schülke, 2018

Kocian, Matúš & Schülke, Michael, 2018, New species and records of Ischnosoma Stephens (Coleoptera: Staphylinidae: Tachyporinae) from Nepal, Zootaxa 4442 (4), pp. 501-522 : 507

Ischnosoma schmidti Kocian & Schülke , sp. n.

Figs 6 , 10 , 18–20 , 24 .

Description. Body dark-brown, pronotum, humeral portions and posterior margins of elytra, and posterior margins of tergites paler yellowish-brown. Legs, palpi and antennomere I brownish-yellow, antenna from antennomere II darker, brown. Pronotum, elytra, and abdomen with weak bluish hue ( Fig. 6 ).

Habitus as in Figs 6 , 10 . Head 0.55–0.58 mm wide; 0.57–0.58 times as wide as pronotum, as wide as long. Eyes large, slightly protuberant, much longer than temples. Surface smooth, frons with very inconspicuous sparse microsculpture. Ocular puncture small with short seta. Antenna 1.51–1.61 mm long. Antennomeres IX–X distinctly longer than wide.

Pronotum 0.94–0.98 mm wide; 0.83–0.88 mm long; 1.1–1.15 times as wide as long, widest in posterior half. Surface with very fine transverse microsculpture, finely and sparsely punctate. Anterior and posterior punctures separated from pronotal margin by 1–2 times the diameter of punctures.

Elytra long, slightly widened posteriad, along suture 0.98–1.06 mm long; 1.17–1.24 times as wide as pronotum; 1.18–1.21 times as long as pronotum. Surface with fine transverse microsculpture. Sutural row with 9– 10 punctures, discal row with 9–12 punctures, lateral row with 10–11 punctures. Wings fully developed.

Abdomen strongly tapering towards apex, in anterior portions of tergites densely, in posterior parts of tergites very sparsely punctate with yellowish pubescence. Posterior margins of tergites and paratergites with very long dark-brown and thick setae. Tergite VII with palisade fringe. Surface with transverse microsculpture.

Length of forebody 2.53–2.65 mm; total body length 4.68–5.18 mm.

Male. Sternite VII in the middle of apical margin straight, not distinctly concave, in postero-median portion without setae ( Fig. 18 ). Sternite VIII in the middle of posterior margin weakly concave, with conspicuously modified chaetotaxy ( Fig. 19 ). Apex of median lobe of aedeagus very slender, in ventral view distinctly pointed ( Fig. 20 ).

Type material. Holotype, male: NEPAL: Prov. Gandaki, Manaslu Mts., Bara Pokhari Lekh, Chhandi Khola Valley , 11.–12.IV.2003, 2000–2300 m NN, leg. Schmidt ( NME).

Paratypes (3): same data as HT, 3♀♀ ( NME, cKoc, cSch).

Etymology. The species is dedicated to Joachim Schmidt (Rostock), collector of the type material.

Distribution. Central Nepal, Manaslu range ( Fig. 24 ).

Remarks. I. schmidti sp. n. belongs to the I. pictum species group. Its habitus somewhat resembles that of I. thamar Kocian. This species is readily distinguished from its congeners by the distinctive male primary and secondary sexual characters.

Figures

FIGURE 24. Distribution of Ischnosoma jumla sp. n. (red diamonds), Ischnosoma bhojpur sp. n. (green squares), Ischnosoma schmidti sp. n. (blue circle) and Ischnosoma hirtei sp. n. (yellow triangle).

FIGURES 2–7. Habitus of Ischnosoma bhojpur sp. n., Holotype (2); Paratype, darkened specimen (3); Ischnosoma jumla sp. n., Paratype (4); Ischnosoma hirtei sp. n., Holotype (5); Ischnosoma schmidti sp. n., Paratype (6); Ischnosoma fasciatocolle, partially darkened specimen (7). Scale bars: 1 mm.

FIGURES 8–11. Forebody. Ischnosoma hirthei sp. n. (8), I. bhojpur sp. n. (9), I. schmidti sp. n. (10), I. jumla sp. n. (11). Scale bar: 1 mm.

FIGURES 18–20. Ischnosoma schmidti sp. n. Male sternite VII (18); male sternite VIII (19); aedeagus in ventral (left) and lateral view (20). Scale bars: 0.1 mm: a (Figs 18–19), b (Fig. 20).