Lobrathium (Lobrathium) extensum, Assing, 2010

Assing, Volker, 2010, On the Lathrobiina of Taiwan (Coleoptera: Staphylinidae: Paederinae), Beiträge Zur Entomologie = Contributions to Entomology 60 (2), pp. 301-361 : 332-334

Lobrathium (Lobrathium) extensum sp. n. ( Figs 107-117 )

Type material:

Holotype ♂ [somewhat teneral]: " Taiwan, Taichung Hsien, Anmashan , 2120 m, 1.V.1990, A. Smetana [ T36 ] / Holotypus ♂ Lobrathium extensum sp. n., det. V. Assing 2010" (cAss) . Paratype: 1 ♀: same data as holotype (cSme) .

Description:

Body length 7.0- 8.3 mm. Habitus as in Fig. 107 . Coloration: body blackish-brown to black; elytra with moderately large reddish-yellow spot of subtriangular shape (i.e., reaching further anteriad laterally than near suture) near posterior margin; legs reddish to reddish-brown; antennae reddish-brown.

Head approximately 1.05 times as long as wide, widest behind eyes; lateral contours regularly convex behind eyes in dorsal view, i.e., posterior angles obsolete ( Fig. 108 ); punctation coarse and relatively dense, sparser in median dorsal portion and on frons; interstices without microsculpture; eyes relatively small and weakly convex, 0.30-0.35 times the length of postocular region from posterior margin of eyes to neck in dorsal view. Antenna slender, approximately 2.5 mm long; antennomere X more than 1.5 times as long as wide ( Fig. 109 ).

Pronotum slender, approximately 1.35 times as long as broad and approximately 0.95 times as broad as head ( Fig. 108 ); punctation similar to that of head or slightly finer; midline rather broadly impunctate; interstices without microsculpture.

Elytra approximately 0.9 times as long as pronotum ( Fig. 108 ); submarginal line present, but of variable length; punctation moderately coarse, not conspicuously dense, well-defined, and arranged in more or less irregular series.

Abdomen approximately as broad as elytra; punctures of anterior impressions of tergites I-IV rather large, but shallow and sparse, punctation of remainder of tergal surfaces fine and dense; interstices with microsculpture; posterior margin of tergite VII with palisade fringe.

♂: posterior margin of tergite VIII obtusely angled in the middle; sternite VII with shallow median impression posteriorly, pubescent everywhere, posterior margin broadly concave ( Fig. 110 ); sternite VIII with oblong median impression, this impression with two oblong clusters of numerous peg-setae, posterior excision broadly U-shaped ( Fig. 111 ); segments IX-X remarkably long and slender ( Fig. 112 ); aedeagus 1.95 mm long, conspicuously long and slender ( Figs 113-114 ).

♀: posterior margin of tergite VIII indistinctly angled in the middle ( Fig. 115 ); sternite VIII approximately as long as wide and as long as tergite VIII, posterior margin broadly convex, in the middle truncate ( Fig. 116 ); segments IX-X slender; tergite IX undivided anteriorly; tergite X truncate anteriorly, very long, approximately 5 times as long as tergite IX in the middle ( Fig. 117 ).

Comparative notes:

This species is distinguished from all its congeners particularly by the morphology of the conspicuously long aedeagus, as well as by the shape and chaetotaxy of the male sternites VII-VIII and of the male segments IX-X. From other Taiwanese Lobrathium species with a reddish elytral spot, it is additionally separated by the longer and more slender antennae, the slender pronotum, as well as by the slender female segments IX-X.

Etymology:

The specific epithet (Latin, adjective: stretched) refers to the conspicuously long aedeagus and the elongated male abdominal segments IX-X.

Distribution and natural history:

The type locality is situated in the Anmashan, Taichung Hsien, northern central Taiwan, at an altitude of 2120 m. The specimens were sifted from leaves accumulated after long lasting rains along a road margin in a mixed forest. The holotype is somewhat teneral .

Figures

Figs 107-117: Lobrathium extensum sp. n.: habitus (107); forebody (108); antenna (109); male sternite VII (110); male sternite VIII (111); male tergites IX-X (112); aedeagus in lateral and in ventral view (113- 114); female tergite VIII (115); female sternite VIII (116); female tergites IX-X (117). Scale bars: 107-108: 1.0 mm; 109-117: 0.5 mm.