Orsunius parvexcisus, Assing, 2011

Assing, V., 2011, Orsunius gen. nov. from the Oriental region (Coleoptera: Staphylinidae: Paederinae: Medonina), Linzer biologische Beiträge 43 (1), pp. 221-244 : 233-234

Orsunius parvexcisus nov.sp. ( Figs 41-49 )

T y p e m a t e r i a l: Holotype Ƌ: " India, Goa , Canacona distr., 100 m, Primärwald, 6.- 10.I.1997, leg. Schulz & Vock / Holotypus Ƌ Orsunius parvexcisus sp.n. det. V. Assing 2011" (cAss) . Paratypes: 1Ƌ: same data as holotype (cAss) ; 1Ƌ: "548 Nepal: Chitwan Distr. , Chitwan N.P.: Sauraha, 150 m, 31.V.-1.VI.1997, leg. W. Schawaller " ( SMNS) .

D e s c r i p t i o n: Rather small species; body length 3.6-3.8 mm. Coloration: head, pronotum, and abdomen reddish; elytra reddish-yellow, in anterior two thirds weakly infuscate, this infuscate spot crossing suture, but not reaching lateral and anterior margins; legs yellowish; antennae reddish-yellow.

Head approximately 1.2 times as broad as long ( Fig. 41 ); punctation rather fine, shallow, and dense ( Fig. 42 ), posterior median portion of dorsal surface with small area with sparse punctation; interstices glossy; sides of head with numerous long black setae. Eyes large and bulging, of somewhat variable size, slightly shorter (holotype) to longer (paratypes) than postocular portion in dorsal view. Gular sutures somewhat curved, at narrowest point separated by a distance of approximately the width of antennomere III.

Pronotum moderately transverse, 1.15 times as wide as long and approximately 0.95 times as broad as head ( Fig. 41 ); posterior angles rounded, weakly marked; lateral margins visible only in posterior two thirds when viewed from above; punctation similar to that of head; midline narrowly impunctate ( Fig. 43 ); lateral margins with numerous long black setae.

Elytra approximately 1.1 times as long as pronotum ( Fig. 41 ); punctation moderately dense, of similar size and depth as that of pronotum; interstices without microsculpture; lateral margins with long black setae. Hind wings fully developed. Tarsi short; protarsomeres rather weakly dilated; metatarsomere I longer than II and slightly shorter than the combined length of II and III.

Abdomen narrower than elytra; punctation extremely fine and dense, slightly less dense on posterior tergites; interstices with pronounced microsculpture; posterior margin of tergite VII with palisade fringe.

Ƌ: sternite VII with weakly concave posterior margin, otherwise unmodified ( Fig. 44 ); sternite VIII short, broader than long, posterior margin weakly excised in the middle ( Fig. 45 ); sternite IX as in Fig. 46 ; aedeagus approximately 0.5 mm long; ventral process large, symmetric, and of distinctive shape.

E t y m o l o g y: The specific epithet (adjective) is composed of the Latin adjectives parvus and excisus and refers to the small posterior excision of the male sternite VIII.

C o m p a r a t i v e n o t e s: This species is characterized particularly by the dense, fine, and shallow punctation of the head and pronotum, as well as by the shape of the male sternite VIII and the morphology 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: The species was found in Goa province , southwestern India, and in Chitwan District , southern central Nepal. The specimens from Goa were collected in a primary forest at an altitude of 100 m ; the paratype from Nepal was discovered at an altitude of 150 m.

Head approximately 1.2 times as broad as long, weakly dilated posteriad ( Fig. 51 ); posterior margin weakly concave in the middle; punctation coarse and sparse ( Fig. 52 ); interstices glossy, in most of dorsal surface broader than diameter of punctures; sides of head with long black setae. Eyes large and bulging, approximately as long as postocular portion in dorsal view.

Figures

Figs 41-49: Orsunius parvexcisus nov.sp.: (41) forebody; (42) median dorsal portion of head; (43) median dorsal portion of pronotum; (44) male sternite VII; (45) male sternite VIII; (46) male sternite IX; (47-48) aedeagus in lateral view; (49) ventral process of aedeagus in ventral view. Scale bars: 41: 0.5 mm; 44-45, 47-49: 0.2 mm; 42-43, 46: 0.1 mm.

Figs 50-56: Orsunius pravus nov.sp.: (50) habitus; (51) forebody; (52) anterior median portion of head in dorsal view; (53) median portion of pronotum; (54) male sternite VIII; (55-56) aedeagus in lateral and in ventral view. Scale bars: 50: 1.0 mm; 51: 0.5 mm; 52-56: 0.2 mm.