Lobrathium bisagittatum, Assing, 2010

Assing, Volker, 2010, On the Lathrobiina of Taiwan (Coleoptera: Staphylinidae: Paederinae), Beiträge Zur Entomologie = Contributions to Entomology 60 (2), pp. 301-361 : 349-351

Lobrathium bisagittatum sp. n. ( Figs 195-202 )

Type material:

Holotype ♂: " Taiwan, Ilan Hsien, Taipingshan , 1820 m, 15.VII.93, A. Smetana [ T153 ] / Holotypus ♂ Lobrathium bisagittatum sp. n., det. V. Assing 2010" (cSme) . Paratypes: 1 ♂: same data as holotype (cSme) ; 1 ♂: " Taiwan, Ilan Hsien, Taipingshan , 1950 m, 13.VII.93, A. Smetana [ T150 ]" (cSme) ; 1 ♂: " Taiwan, Taoyuan Hsien, Takuanshan For., 17.IV.90, 1600 m, A. Smetana [ T3 ]" (cAss) .

Description:

Body length: 8.0-9.0 mm. Habitus as in Fig. 195 . Coloration as in L. furcillatum .

Head weakly oblong, approximately 1.05 times as long as wide; posterior angles obsolete, broadly rounded ( Fig. 196 ); punctation relatively coarse and dense (but less so than in L. furcillatum ), sparser in median dorsal area and on frons; interstices without microsculpture. Eyes moderately large, approximately half the distance from posterior margin of eyes to posterior constriction in dorsal view. Antennae of similar morphology as that of L. stimulansstimulans ( Fig. 197 ).

Pronotum approximately 1.2 times as long as broad and approximately as broad as head or nearly so ( Fig. 196 ); punctation slightly coarser and slightly less dense than that of head; midline narrowly impunctate.

Elytra short, approximately 0.7 times as long as pronotum; humeral angles practically obsolete ( Fig. 196 ); lateral parts with fine submarginal carina; punctation very coarse and dense; interstices without microsculpture. Hind wings completely reduced.

Abdomen approximately 1.05 times as wide as elytra; punctation fine and dense; interstices with fine microreticulation; posterior margin of tergite VII without palisade fringe.

♂: posterior margin of tergite VIII in the middle with small, but compicuous narrow and acute process ( Fig. 198 ); sternite VII indistinctly depressed in the middle, posterior margin weakly

concave; sternite VIII with long and moderately narrow median impression, this impression with two long clusters of numerous peg-setae, posterior excision not very deep and broadly V-shaped ( Fig. 199 ); aedeagus of highly characteristic morphology ( Fig. 200-202 ).

♀: unknown.

Comparative notes:

This species is distinguished from L. furcillatum and L. cornutissimum by the coarser and less dense punctation of the head and the pronotum, the narrower, more coarsely punctate, and more glossy elytra, the more slender abdomen, and by the male sexual characters, particularly the median process at the posterior margin of the male tergite VIII and the distinctive shape of the aedeagus. In external appearance (slender habitus, coarse punctation, glossy forebody), it is similar to some of the following species, but separated from them by the presence of lateral submarginal carinae of the elytra and by the sexual characters.

Etymology:

The specific epithet is composed of the Latin prefix bi- (two) and an adjective derived from the Latin noun sagitta (arrow) and alludes to the shape of the apical lobes of the aedeagus.

Distribution and natural history:

The species was collected in the Taipingshan and the Takuanshan, Ilan and Taoyuan Hsien, northern Taiwan, at altitudes of 1600-1950 m. The material was sifted from thick layers of moss on fallen trees, leaf litter, and other debris, partly near a stream, in a coniferous forest and a secondary, mostly coniferous forest. The specimens found in July are partly teneral.

Figures

Figs 193-202: Lobrathium cornutissimum sp. n. (193-194) and L. bisagittatum sp. n. (195-202): female sternite VIII (193); female tergites IX-X (194); habitus (195); forebody (196); male abdominal segments VII-VIII in dorsal view (198); male sternite VIII (199); aedeagus in lateral and in ventral view (200-202). Scale bars: 195-197: 1.0 mm; 193-194, 198-202: 0.5 mm.