Lobrathium (Lobrathium) penicillatum, Assing, 2010

Assing, Volker, 2010, On the Lathrobiina of Taiwan (Coleoptera: Staphylinidae: Paederinae), Beiträge Zur Entomologie = Contributions to Entomology 60 (2), pp. 301-361 : 336-338

Lobrathium (Lobrathium) penicillatum sp. n. ( Figs 124-133 )

Type material:

Holotype ♂: " Taiwan, Nantou Hsien, Shanlinchi , 1650 m, 19.V.1991, A. Smetana [ T87 ] / Holotypus ♂ Lobrathium penicillatum sp. n., det. V. Assing 2010" (cSme) . Paratypes: 2 ♂ ♂, 5 ♀ ♀ [1 ♂ teneral]: same data as holotype (cSme, cAss) .

Description:

Body length 5.5-7.0 mm. Habitus as in Fig. 124 . Coloration: body blackish; elytra sometimes with weak bluish hue, with moderately large (size similar to that of eyes) reddish-yellow spot of subcircular to oval shape near posterior margin; legs blackish brown with paler tarsi; antennae dark-brown, antennomere I blackish, apical 2-4 antennomeres usually reddish to reddish-brown.

Head approximately as long as wide or weakly oblong, widest across eyes; behind eyes convexly tapering posteriad in dorsal view, posterior angles almost obsolete ( Fig. 125 ); punctation coarse and dense, sparser in median dorsal portion and on frons; interstices without microsculpture; eyes large and bulging, 0.7-0.8 times the length of postocular region from posterior margin of eyes to neck in dorsal view. Antenna moderately slender, approximately 1.8 mm long; antennomere X almost 1.5 times as long as wide ( Fig. 126 ).

Pronotum slender, approximately 1.3 times as long as broad and 0.9 times as broad as head ( Fig. 125 ); punctation as coarse as that of head or nearly so and moderately sparse, sparser than that of head; impunctate midline more or less narrow; interstices without microsculpture.

Elytra long, 1.05-1.10 times as long as pronotum ( Fig. 125 ); submarginal line present; punctation coarse, dense, well-defined, not distinctly arranged in series.

Abdomen slightly narrower than elytra; punctures in anterior impressions of tergites I-IV large, those of anterior impression of tergite III deep and defined, those of anterior impressions of tergites IV-VI shallow and ill-defined; remainder of tergal surfaces with fine and moderately dense punctation; interstices with microsculpture; posterior margin of tergite VII with palisade fringe.

♂: posterior margin of tergite VIII obtusely angled in the middle; sternite VII with median impression, posterior margin weakly concave, in the middle with weakly convex projection ( Fig. 127 ); sternite VIII posteriorly with deep impression, this impression with a cluster of numerous pegsetae, on either side of impression with conspicuous tuft of long black setae; posterior excision large, deep, and U-shaped ( Fig. 128 ); aedeagus approximately 1.1 mm long, with very broad and apically bifid ventral process in ventral view ( Figs 129-130 ).

♀: posterior margin of tergite VIII similar to that of ♂ ( Fig. 131 ); sternite VIII approximately as long as tergite VIII, posterior margin broadly and weakly convex, in the middle truncate

( Fig. 132 ); segments IX-X not particularly slender; tergite IX undivided anteriorly, anterior margin not emarginate in the middle; tergite X of ovoid shape, relatively broad, approximately 5 times as long as tergite IX in the middle ( Fig. 133 ).

Comparative notes:

This species is distinguished from all its congeners particularly by the morphology of the ventral process of the aedeagus, as well as by the shape and chaetotaxy of the male sternite VIII. From other Taiwanese Lobrathium species with a reddish elytral spot, it is additionally separated by the dark coloration of the legs, and the combination of very long elytra and well-delimited elytral spot of subcircular shape.

Etymology:

The specific epithet is an adjective derived from the Latin noun penicillus (paint-brush) and refers to the conspicuous chaetotaxy of the male sternite VIII.

Distribution and natural history:

The type locality is situated in Nantou Hsien, central Taiwan, at an altitude of 1650 m. The specimens were sifted from deep layers of wet debris, twigs, leaves, and vegetation on a stream bank in a primary broadleaved forest. One of the type specimens is teneral .

Figures

Figs 124-133: Lobrathium penicillatum sp. n.: habitus (124); forebody (125); antenna (126); male sternite VII (127); male sternite VIII (128); aedeagus in lateral and in ventral view (129-130); female tergite VIII (131); female sternite VIII (132); female tergites IX-X (133). Scale bars: 124-125: 1.0 mm; 126-133: 0.5 mm.