Platyprosopus rossii, Assing, 2019

Assing, Volker, 2019, Three new species of Platyprosopus from Thailand, Cambodia, and Sierra Leone, and additional records (Coleoptera, Staphylinidae, Staphylininae), Linzer biologische Beiträge 51 (2), pp. 707-715 : 713

Platyprosopus rossii nov.sp. ( Figs 6-10 )

T y p e m a t e r i a l: Holotype Ƌ: " CAMBODIA - Kampong Chhnang prov., Kampong Chhnang env., Toul Ompel , 12°14'14''N, 104°41'15''E, light trap, 19+ 21. V.2018, leg. Bernardi, Kong & Rossi / Holotypus Ƌ Platyprosopus rossii sp.n. det. V. Assing 2019" (cAss) . Paratypes: 1Ƌ, 1♀, same data as holotype (cAss) ; 1Ƌ: " CAMBODIA - Kampong Chhnang prov., Kampong Chhnang env., Phum Toul Ompel, shore of branch of Tonle Sap Lake , 12°14'N, 104°41'E, light trap, 4+ 7.XI.2018, leg. W. Rossi " (cAss) ; 1♀: " CAMBODIA - Kampong Chhnang prov., Rolea Bi'er distr., Toulkrolanh vill., 12°13'31''N, 104°39'50''E, light trap, 7.XI.2018, leg. W Rossi " (cAss) .

E t y m o l o g y: This species is dedicated to Walter Rossi (Università dell'Aquila), who collected most of the material that this paper is based on.

D e s c r i p t i o n: Body length 8.5-9.7 mm; length of forebody 4.4-4.9 mm. Coloration: head blackish-brown to black; pronotum dark-reddish to dark-brown; elytra reddish with the anterior portion somewhat darker; abdomen dark-brown to blackishbrown with the posterior margins of tergites III-VII and segments VIII-X reddish; legs reddish-yellow; antennae reddish with the apical half somewhat paler than the basal half.

Head ( Fig. 6 ) approximately 1.15 times as long as broad; lateral margins behind eyes subparallel in dorsal view; dorsal surface with extremely dense and moderately coarse punctation, with the interstices reduced to narrow ridges, rendering the head matt; middle of dorsal surface with or without indistinct and narrow glossy patches. Eyes small, approximately half as long as postocular region in dorsal view. Antenna approximately 2.5 mm long.

Pronotum ( Fig. 6 ) oblong, 1.05-1.15 times as long as broad and approximately as broad as head; anterior margin indistinctly concave; lateral margins parallel or weakly converging in anterior three-fourths in dorsal view; disc with moderately fine and dense punctation, without micropunctation and without dorsal series of macropunctures; disc with a narrow impunctate median band; interstices without microsculpture.

Elytra ( Fig. 6 ) 0.77-0.85 times as long as pronotum; punctation very dense and very fine. Hind wings fully developed. Metatarsomere I as long as the combined length of metatarsomeres II and III; metatarsomeres I and II unmodified (not dilated).

Abdomen slightly narrower than elytra, with extremely dense and somewhat asperate punctation (particularly on tergites IV-VII) and with pronounced microsculpture rendering the surface matt; posterior margin of tergite VII with palisade fringe.

Ƌ: sternite VIII with distinctly concave posterior margin; hemitergites IX and tergite X slender ( Fig. 7 ); apices of hemitergites IX spine-shaped and bent upwards ( Fig. 7 ); sternite IX ( Fig. 8 ) very slender, posterior margin narrowly concave; aedeagus ( Figs 9- 10 ) 1.0 mm long; median lobe moderately broad, with semitransparent apex of broadly convex to triangular shape in ventral view; parameres not reaching apex of median lobe, each with one apical seta.

C o m p a r a t i v e n o t e s: Platyprosopus rossii is readily distinguished from other congeners known from the Oriental region by the combination of relatively small body size, a slender habitus, rather small eyes, very dense punctation of the whole body, a slender male sternite IX with a narrowly concave posterior margin, and particularly by the shape of the aedeagus.

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: This species is currently known from two geographically close localities to the south of Tonle Sap Lake, Kampong Chhnang province, Cambodia. In the type locality, which is identical to that of of several species of Paederinae (e.g., ASSING 2018a, b), P. rossii was collected together with P. indicus , P. fraternus , P. socius , and three females of an unidentified (undescribed?) species. All the specimens were collected with light traps.

Figures

Figs 6-10: Platyprosopus rossii: (6) forebody; (7) male tergites IX-X; (8) male sternite IX; (9-10) aedeagus in lateral and in ventral view. Scale bars: 6: 1.0 mm; 7-10: 0.5 mm.