Orsunius gladiator, Assing, 2014

Assing, V., 2014, On Orsunius II. Eight new species and additional records (Coleoptera: Staphylinidae: Paederinae: Medonina), Linzer biologische Beiträge 46 (1), pp. 461-479 : 467

Orsunius gladiator nov.sp.

( Figs 9 , 14-17 , Map 2 )

Type material Holotype: " Thailand, 23.-25.ii.1996, Ranong prov. 9°56' 98°40', Ranong: Hot Springs , K. Majer leg. / Holotypus Orsunius gladiator sp.n. det. V. Assing 2013" ( NHMB) . Paratype: "N-Thailand, Chiang Mai, Sandoeng [=Samoeng?], Flussufer, 350-550 m, Sand, Steine, 12.XI.1995, P. Wunderle" (cAss).

Etymology: The specific epithet (Latin, noun in apposition) alludes to the swordshaped ventral process of the aedeagus.

Description: Body length 4.0- 4.9 mm; length of forebody 2.2-2.4 mm. Habitus as in Fig. 14 . Coloration: head dark-reddish; pronotum bright-reddish; elytra reddishbrown with the posterior two-fifths and the humeral angles reddish-yellow; abdomen brown, with the posterior portion of segment VII and all of segment VIII dark-yellowish; legs yellowish; antennae reddish.

Head ( Fig. 15 ) strongly transverse, approximately 1.25 times as broad as long, broadest across eyes, weakly tapering behind eyes, and with sharply marked posterior angles; posterior margin very weakly concave in the middle; punctation moderately dense and very coarse, median dorsal portion with a subcircular impunctate patch; interstices without microsculpture; lateral margins with long black setae (broken off in holotype). Eyes large and strongly bulging, somewhat longer than postocular portion in dorsal view. Antennae 1.2 mm long and slender; preapical antennomeres approximately as broad as long. Anterior margin of labrum with V-shaped excision in the middle.

Pronotum ( Fig. 15 ) 1.15 times as wide as long and slightly broader than head; posterior angles rounded, weakly marked; lateral margins with long black setae (broken off in holotype); punctation moderately dense and coarse, but slightly less so than that of head; midline with narrow impunctate band; interstices without microsculpture.

Elytra ( Fig. 15 ) approximately as long as pronotum; punctation dense and fine; interstices without microsculpture. Hind wings fully developed. Protarsomeres I-IV distinctly dilated. Metatarsomere I moderately slender, longer than II, but shorter than the combined length of II and III.

Abdomen slightly narrower than elytra; punctation dense and extremely fine; interstices with distinct microreticulation; posterior margin of tergite VII with palisade fringe.

: sternite VII with weakly concave posterior margin; sternite VIII ( Fig. 9 ) approximately 1.05 times as long as broad and with barely noticeable, extremely shallow and broad posterior excision; aedeagus ( Figs 16-17 ) 0.73 mm long, ventral process conspicuously long and slender, sword-shaped in lateral view.

Comparative notes: In size, coloration, and habitus, O. gladiator somewhat resembles O. immsi , from which it is distinguished by the distinctly coarser punctation of the more transverse head, as well as by the completely different male sexual characters.

Distribution and natural history: The species is known from two localities in northern and southern Thailand ( Map 2 ). The slightly teneral paratype was collected on a river bank with sand and stones at an altitude of 350- 550 m. The holotype was collected together with O. latexcisus , O. immsi , O. flavovirgatus , and an undescribed species.

Figures

Map 2: Distributions of Orsunius gladiator (white and black circles), O. latexcisus (black circle), O. flavovirgatus (black circle), O. heissi (black star), O. stimulans (black and grey triangles), O. granulosus (white and grey triangles), O. cuneatus (white diamond), and O. spathulatus (black square).

Figs 1-9: Orsunius spathulatus nov.sp. (1-6), O. stimulans nov.sp. (7-8), and O. gladiator nov.sp. (9): (1) habitus; (2) forebody; (3, 8, 9) male sternite VIII; (4) posterior portion of male sternite VIII; (5) aedeagus in lateral view; (6) ventral process in ventral view; (7) male sternite VII. Scale bars: 1- 2: 1.0 mm; 3-9: 0.2 mm.

Figs 10-17: Orsunius stimulans nov.sp. (10-13) and O. gladiator nov.sp. (14-17): (10, 14) habitus; (11, 15) forebody; (12, 16) aedeagus in lateral view; (13) aedeagus in ventral view; (17) ventral process in ventral view. Scale bars: 10-11, 14-15: 1.0 mm; 12-13, 16-17: 0.2 mm.