Pseudolathra sagittata, Assing, 2012

Assing, V., 2012, The Pseudolathra species of the East Palaearctic and the Oriental regions (Coleoptera: Staphylinidae: Paederinae), Beiträge Zur Entomologie = Contributions to Entomology 62, pp. 299-330 : 324-326

Pseudolathra sagittata sp. n. ( Figs 59-63 , Map 2 )

Type material:

Holotype ♂: “W. Thailand: 300 m., Thung Yai Wildlife Sanctuary , 15°28'N - 98°48'E / Tak Province, Umphang District , Song Bae Stream . 18-27.iv.1988. / Evergreen rain forest. M.J.D. Brendell. B.M. 1088-183 / Flight interception trap / Holotypus ♂ Pseudolathra sagittata sp. n., det. V. Assing 2012“ ( BMNH) . Paratypes: 2 ♂♂, 2 ♀♀: same data as holotype ( BMNH, cAss) ; 2 ♂♂: “W. Thailand: 300 m., Thung Yai Wildlife Sanctuary, 15°30'N - 98°48'E / Tak Province, Umphang District, Mae Chan / Mae Klong confluence. 27.iv.-6.v.1988. / Oak/bamboo forest. M.J.D. Brendell. B.M. 1088-183 / Flight interception trap “ ( BMNH, cAss) .

Etymology:

The specific epithet (Latin, adjective: arrow-shaped) refers to the shape of the apex of the dorsal plate of the aedeagus.

Description:

Body length 6.5-7.5 mm; length of forebody 3.5-4.0 mm. Habitus as in Fig. 59 . Coloration: body black; legs dark-yellowish; antennae pale-reddish.

Head ( Fig. 60 ) strongly transverse, 1.20-1.25 times as wide as long; posterior angles obtusely marked; dorsal surface conspicuously glossy, almost impunctate, except for a few punctures near eyes and near posterior margin. Eyes large and bulging, 3-4 times as long as postocular region in dorsal view. Antenna approximately 2.3 mm long; antennomeres III-X with very narrow bases, distinctly dilated apically.

Pronotum ( Fig. 60 ) almost as broad as long and approximately as broad as head; dorsal series composed of usually 5-6 coarse punctures; lateral portions with very sparse coarse punctures; surface conspicuously glossy.

Elytra ( Fig. 60 ) 0.90-0.95 times as long as pronotum; laterally with fine and complete submarginal carina; punctation arranged in three series, one along suture, one in the middle, and one near lateral margin; interstices without microsculpture and very glossy. Hind wings fully developed. Protarsomeres without appreciable sexual dimorphism, in both sexes strongly dilated.

Abdomen distinctly narrower than elytra; punctation rather coarse and very dense on tergite III, gradually becoming finer and less dense on tergites IV-VII; interstices without microsculpture and glossy; posterior margin of tergite VII with palisade fringe.

♂: sternite VII not distinctly modified; sternite VIII oblong, posterior excision narrow and deep, not quite reaching middle of sternite ( Fig. 63 ); aedeagus 1.0- 1.1 mm long, slender, with apically deeply bifid ventral process, and with apically somewhat arrow-shaped dorsal plate in ventral view ( Figs 61-62 ).

Comparative notes:

In external appearance, P. sagittata somewhat resembles P. nigerrima , from which it is distinguished by smaller size (no overlap), paler legs, the distinctly coarser punctation of the anterior abdominal tergites, as well as by the sexual characters, particularly the completely different shape of the aedeagus.

Distribution and natural history:

Pseudolathra sagittata is known from two localities in western Thailand ( Map 2 ). The specimens were collected with flight interception traps in an evergreen rain forest and in a mixed oak and bamboo forest at an altitude of 300 m.

Figures

Map 2: Distributions of Pseudolathra himalayana (filled triangles), P. nigerrima (open squares), P. sagittata (open diamond), and P. regularis (filled circles), based on revised records.

Figs 59-62: Pseudolathra sagittata: habitus (59); forebody (60); aedeagus in lateral and in ventral view (61-62). Scale bars: 59-60: 1.0 mm; 61-62: 0.5 mm.

Figs 63-70: Pseudolathra sagittata (63) and P. regularis (64-70), lectotype (64-65, 67-68, 70) and male from China (66, 69): male sternite VIII (63, 66); habitus (64); forebody (65); aedeagus in lateral and in ventral view (67-69); dorsal plate of aedeagus in dorsal view (70). Scale bars: 64-65: 1.0 mm; 63, 66-70: 0.5 mm.