Scaphisoma strigatum, Löbl, 2023

Löbl, Ivan, 2023, New species and records of Scaphidiinae (Coleoptera: Staphylinidae) from mainland China and Taiwan, Vernate 42, pp. 135-142 : 137-139

Scaphisoma strigatum sp. nov.

Holotype female, China. S - Yunnan (Xishuangbanna) MF 1. 23 km NW Jinhong, vic. Na Ban ( NNNR) / N22°09.49, E100°39.92 23.v. 2008, 730 m, transition zone leg. A. Weigel ( NMEG).

Description. Length 2.52 mm, width 1.53 mm. Head and most of body light reddish-brown, apical fifth of elytra and tip of abdomen yellowish, legs ochraceous, lighter than thorax, antennae yellowish. Length/width ratios of antennomeres: III 13/10: IV 25/8: V 42/9: VI 58/12: VII 68/17: VIII 50/11: IX 65/15: X 61/17: XI 74/16. Pronotum lacking microsculpture, with lateral margins arcuate; lateral margin carina concealed in dorsal view, punctate; discal punctation dense and fine, visible at 20 times magnification, puncture diameters mostly about two to three times as large as puncture diameters. Exposed tip of scutellum minute. Elytron dull, with strigulate microsculpture; weakly narrowing apicad, with lateral margin arcuate, lateral margin carina barely visible in dorsal view, punctate; apical margin weakly rounded, apical crenulation distinct; inner apical angle situated in level of outer angle; sutural margin not raised; sutural stria shallow, parallel to suture, curved at side of pronotal lobe and extending along base to form basal stria reaching basal mid-width; adsutural area flat, about 0.08 mm wide shortly posteriad of scutellar tip, irregularly, finely punctate; discal punctation hardly coarser than pronotal punctation, rather sparse, with puncture intervals mostly about four to five times as large as puncture diameters. Hind wings fully developed. Hypomeron smooth.

Mesanepisternum extremely finely and sparsely punctate. Mesoventrite very finely punctate, lacking punctures along lateral margins. Mesepimeron about 3 times as long as wide and as long as interval between its tip and mesocoxa. Metaventrite lacking microsculpture, flattened in middle, lacking impressions, with punctation dense and rather coarse on apicomedian area, distinct at 30 times magnification, with punctures to part as large as puncture intervals, becoming sparse and very fine anteriad and laterad; antecoxal puncture rows absent; submesocoxal areas nearly 0.05 mm long, about as long as fourth of shortest interval between its margin and metacoxa; submesocoxal lines convex, finely punctate. Metanepisternum lacking microsculpture, flat, narrowing anteriad, suture impressed, oblique. Tibiae straight. Exposed tergites and ventrites sparsely, very finely punctate and with strigulate microsculpture evanescent on basolateral areas of tergite I. Pygidium not notched, with apical margin truncate. Ventrite I with submetacoxal areas 0.10 mm long, nearly as long as half of shortest interval between its margin and apical margin of ventrite, with punctulate microsculpture; submetacoxal lines subtriangular.

Etymology. The species epithet is a Latin adjective referring to the strigulate microsculpture of the elytra.

Comments. None of the Scaphisoma described from continental Asia has elytra bearing microsculpture, while the presence of microsculpture on abdomen is a common feature. A single species possessing this feature was included in the key to Chinese Scaphisoma (Löbl, 2019) , as “sp. near S. pecki ”. As it was, and still is, represented by only a single specimen, its formal description was delayed in expectation of additional specimens. Meantime, a second Chinese species with the same type of elytral microsculpture was found (see below). Therefore, formal descriptions of these species are considered justified. Scaphisoma strigatum may be easily distinguished from the Japanese S. pecki Löbl, 1982 , which also possesses elytra with microsculpture and has basal striae, by the larger size of the body, the antennomeres X and XI similar in length, the pronotum finely punctate, the submetaxocal lines subtriangular and not conspicuously punctate, and the abdomen with strigulate microsculpture. The elytral microsculpture of S. pecki is imbricate, reliably distinguishing the species.