Scaphisoma submaculatum Pic, 1920

Löbl, Ivan, 2015, Notes on Scaphisoma of Kalimantan (Coleoptera: Staphylinidae: Scaphidiinae), Acta Entomologica Musei Nationalis Pragae 55 (1), pp. 129-144 : 139-140

Scaphisoma submaculatum Pic, 1920

( Figs 6–8 )

Scaphosoma submaculatum Pic, 1920: 24 .

Type locality. Indonesia, Kalimantan, Martapura, Riam Kanan .

Type material examined. LECTOTYPE (by present designation): ♂, ‘ Riam Kanan Martapoera Z. O. Borneo Doherty VI, VII [printed] / type [handwritten by Pic] / Baeocera probab [handwritten by Pic] / sp. de la divin 1–2 [handwritten by Pic] / submaculatum Pic [handwritten by Pic] / TYPE [red, printed] / Lectotype Scaphisoma submaculatum Pic des. Löbl, 2014’ ( MNHN).

Redescription. Length 1.90 mm, width 1.32 mm. Head and body reddish-brown, elytra slightly darkened posterior mid-length and along lateral margins, in apical fifth lighter, almost yellowish. Mesoventrite and metaventrite somewhat darker than pronotum. Abdomen becoming lighter apically, as femora and tibiae lighter than pronotum. Pronotum, elytra, hypomera, mesoventrite and metaventrite lacking microsculpture. Antennae with length/width ratio of antennomeres as follows: III 18/8: IV 37/6: V 50/6.5: VI 60/7: VII 65/12: VIII 58/7: IX 62/11: X 60/13 (left antennomere XI and right antennomeres VII–XI missing). Pronotum with lateral margins rounded, lateral margin carinae not visible in dorsal view, discal punctation very fine, punctures dense, not well delimited, pubescence indistinct. Point of scutellum exposed. Elytra with lateral margin carinae exposed in dorsal view, apical margins slightly rounded, inner apical angle not prominent, situated somewhat posterior level of outer angles, sutural margin not raised, sutural striae deep, curved at base and extending laterally pronotal lobe, converging apically, adsutural areas flat, with single puncture row, near scutellum combined 0.16 mm, at mid-length combined 0.12 mm wide. Elytral punctation very fine and dense anterior mid-length, similar to pronotal punctation, punctation posterior elytral mid-length less fine, consisting of punctures fairly well delimited, with puncture intervals mostly about twice to three times as large as puncture diameters. Hypomera smooth. Mesepimeron about as long as half of interval to mesocoxa, about 2.5 times as long as wide. Metaventrite convex in middle, lacking impressions or sulci; punctation even, very fine and sparse. Submesocoxal areas 0.04 mm, about as fifth of interval to metacoxa, submesocoxal lines convex, only with few fine marginal punctures; antecoxal puncture rows present, in impressed lines. Metanepisternum flat, in level with metaventrite, 0.14 mm wide, moderately narrowed anteriad, with inner margin somewhat arcuate, at angles rounded. Protibiae straight, mesotibiae and metatibiae slightly bent in apical halves. Basomedian area of abdominal ventrite 1 with fairly coarse punctures, remainder of abdomen very finely punctate, abdominal microsculpture strigulate. Submetacoxal areas 0.08 mm, somewhat shorter than half of interval to apical margin of ventrite 1, submetacoxal lines convex, with fine margin punctures.

Male characters. Tarsomeres 1 to 3 of protarsi slightly widened. Aedeagus ( Figs 6–8 ) 1.01 mm long, symmetrical. Median lobe with basal bulb weakly sclerotized, very large, overlapping apical process, lacking prominent articular process. Apical process bifurcate, perpendicular to axis of basal bulb, strongly sclerotized, near tip very narrow and abruptly bent, with ventral denticle (lateral view). Parameres wide, lobed, arcuate in dorsal view, overlapping apically, membranous inner lobes finely striate. Internal sac lacking flagellum, bearing complex denticulate structures.

Distribution. Indonesia (Kalimantan).

Comments. This species is a member of the S. binhanum group (see LÖBL 1979), well characterized by its aedeagal features, in particular by the unique shape of the apical process of the median lobe, as seen in lateral view.

Figures

Figs 6–8. Adeagus of Scaphisoma submaculatum Pic, 1920 in dorsal view (6), paramere in ventral view (7), apical part of aedeagus in lateral view (8). Scale bars = 0.2 mm.