Oedichirus latexciscus, Assing, 2014

Assing, V., 2014, On the Oedichirus fauna of China (Coleoptera: Staphylinidae: Paederinae), Linzer biologische Beiträge 46 (2), pp. 1229-1240 : 1230-1231

Oedichirus latexciscus nov.sp. ( Figs 1-8 , Map 1 )

T y p e m a t e r i a l: Holotype: " CHINA [1a] - Yunnan, mts NW Dongchuan, 2350 m, 26°10'00''N, 103°03'32''E, trail side, 8.VIII.2014, V. Assing / Holotypus Oedichirus latexcisus sp.n. det. V. Assing 2014" (cAss).

E t y m o l o g y: The specific epithet is an adjective composed of the Latin adjective latus (broad) and the past participle of the Latin verb excidere (to cut out). It alludes to the broad posterior excision of the male sternite VIII, one of the characters distinguishing this species from the similar O. flammeus .

D e s c r i p t i o n: Large species; body length 11.5 mm; length of forebody 5.0 mm. Coloration: forebody body reddish-brown; abdomen with segments III-VII dark-brown and segments VIII-X reddish-brown; legs, antennae, and maxillary palpi pale-yellowish.

Head ( Fig. 1 ) approximately 1.15 times as broad as long, broadest across eyes; lateral contours behind eyes smoothly curving towards posterior constriction, posterior angles obsolete; dorsal surface with moderately sparse and irregular coarse punctures, posteromedian area and frons impunctate. Eyes strongly convex, slightly longer than distance from posterior margin of eye to posterior constriction. Antenna 3.5 mm long and shaped as in Fig. 1 .

Pronotum ( Fig. 1 ) 1.22 times as long as broad and approximately 1.05 times as broad as head, widest anteriorly and distinctly tapering posteriorly; punctation similar to that of head; median portion of pronotum with two series of punctures situated in a furrow, these series separated by a distance of approximately one-fourth the width of pronotum; area between theses series anteriorly with moderately dense coarse punctures and posteriorly impunctate.

Elytra ( Fig. 1 ) short, 0.67 times as long as pronotum and depressed; humeral angles completely obsolete; punctation very coarse and dense. Hind wings completely reduced.

Abdomen ( Fig. 3 ) slightly broader than elytra; punctation irregular, not arranged in transverse rows, coarse and dense on tergites III-VI, sparser and less deep on tergites VII-VIII; anterior impressions of tergites III-VI without longitudinal keels; anterior impressions of tergites III-VII with pronounced reticulate microsculpture, remainder of tergal surfaces with very shallow and fine microsculpture composed of transverse striae; microsculpture of tergite VIII composed of transverse meshes; posterior margin of tergite VII without palisade fringe.

: sternite VII ( Figs 4-5 ) with an impression of subtriangular shape in postero-median portion, this impression nearly impunctate and laterally delimited by a moderately pronounced oblique fold on either side, posterior margin weakly concave in the middle; sternite VIII ( Figs 4-5 ) strongly impressed in postero-median portion and with a pair of pronounced oblique folds in the middle, median portion without setae, posterior margin with broad, not very deep, and slightly asymmetric median excision; tergite IX ( Fig. 6 ) with pair of rather long and acute posterior processes, these processes approximately 0.85 times as long as median portion of tergite IX; aedeagus ( Figs 7-8 ) 1.8 mm long; ventral process apically obliquely and asymmetrically truncate in ventral view, subapically with two conspicuous processes of completely different shapes, the left process (ventral view) long, asymmetrically spear-shaped, and curved apicad, the right process much shorter and apically broadly bifid; parameres moderately long, of different lengths, right paramere (ventral view) longer than left paramere; dorsal plate not distinctly sclerotized.

: unknown.

C o m p a r a t i v e n o t e s: The similarly modified male primary and secondary sexual characters suggest that O. latexcisus is closely allied to the similarly coloured O. flammeus , from which it differs by smaller body size ( O. flammeus : length of forebody <4.0 mm), the more slender, more densely punctate, and sublaterally more distinctly impressed pronotum, the longer and more slender elytra, the more pronounced impression and folds of the male sternite VII, the broader and less deep posterior excision of the male sternite VIII, and by the differently shaped subapical processes of the aedeagus. In the key by CAMERON (1931), O. latexcisus would key out at couplet 7 together with O. niger CAMERON, 1914 (South India) and O. minor CAMERON, 1914 ( Sri Lanka). The new species is readily distinguished from both of them by the paler coloration and larger size alone, from the former additionally by shorter elytra and from the latter by a much more oblong pronotum.

D i s t r i b u t i o n a n d n a t u r a l h i s t o r y: The type locality is situated in a mountain approximately 15 km to the northwest of Dongchuan, Yunnan ( Map 1 ), at an altitude of 2350 m. The specimen was collected by sifting litter and the roots of herbs and grass at and near the margin of a mountain trail.

Figures

Map 1: Distributions of the micropterous Oedichirus species of China: O. abbreviatus (white circles); O. schuelkei (black circles); O. latexcisus (white star); O. flammeus (black star).

Figs 1-6: Oedichirus latexcisus nov.sp.: (1) forebody; (2) antenna; (3) abdominal segments III-VI in dorsal view; (4) male abdominal segments VII-VIII in ventral view; (5) male abdominal segments VII-VIII in lateral view; (6) male tergites IX-X. Scale bars: 1.0 mm.

Figs 7-12: Aedeagi of Oedichirus species in lateral and in ventral view: (7-8) Oedichirus latexcisus nov.sp.; (9-10) O. schuelkei nov.sp.; (11-12) O. abbreviatus nov.sp. Scale bars: 0.5 mm.