Scaphisoma angulosum, Ivan Löbl & Ryo Ogawa, 2016

Ivan Löbl & Ryo Ogawa, 2016, On the Scaphisomatini (Coleoptera, Staphylinidae, Scaphidiinae) of the Philippines, IV: the genera Sapitia ACHARD and Scaphisoma LEACH, Linzer biologische Beiträge 48 (2), pp. 1339-1492 : 1397-1398

5.2.14.1. Scaphisoma angulosum nov.sp. ( Figs 140, 141 )

T y p e m a t e r i a l: Holotype 6: Philippines: Leyte Visca N Baybay, 1991 prim. forest, 200-500m leg. Schawaller et al. / 2.3.91 (SMNS).

Description: Length 1.83 mm, width 1.25 mm. Head, most of body and appendages uniformly ochreous, apical fifth of elytra lighter, yellowish. Pronotum and elytra not microsculptured and not iridescent. Length/width ratio of antennomeres as: III 11/8: IV 45/7: V 64/8: VI 44/9: VII 55/14: VIII 40/9: IX 53/14: X 53/13: XI 67/14. Pronotum with lateral margins evenly rounded, lateral margin carinae almost throughout visible in dorsal view, lateral striae impunctate, punctation dense, very fine, hardly visible at 50 times magnification. Tip of scutellum exposed. Elytra convex, with lateral margin carinae almost entirely visible in dorsal view, apical margins rounded, inner apical angles not prominent, situated posterior level of outer angles; sutural margin not raised, sutural striae deep, slightly converging apically, very finely punctate, not bent at base, basal striae absent; adsutural areas narrow, flat, each with single puncture row, lateral striae impunctate. Elytral disc with punctation sparse and very fine, less fine than that of pronotum, punctures intervals mostly about twice to three times as large as puncture intervals. Hind wings fully developed. Hypomera and mesanepisterna smooth. Mesepimera shorter than halves of intervals to mesocoxae, hardly twice times as long as wide. Metaventrite not microsculptured, very finely punctate, lacking antecoxal puncture row. Median part of metaventrite weakly convex, with two apicomedian impressions. Submesocoxal areas 0.03 mm, about as fifth of intervals to metacoxae, submesocoxal lines parallel, coarsely punctate, punctures not extended by striae. Metanepisternum flat, weakly narrowed anteriad, with inner margin straight, hardly rounded at angles, impressed below margin of metaventrite, suture deep. Protibiae and mesotibiae slightly curved, metatibiae straight, thickened in apical parts. Abdomen with distinct strigulate microsculpture, very finely and sparsely punctate; submetacoxal areas 0.02 mm, about tenth of intervals to apical margin of sternite, submetacoxal lines parallel, coarsely punctate.

M a l e: Protarsomeres and mesotarsomeres 1 to 3 distinctly widened. Aedeagus ( Figs 140, 141 ) 1.0 mm long, fairly strongly sclerotized, symmetrical. Median lobe with basal bulb fairly small, somewhat longer than apical process, articular process ventrally prominent, apical process slightly narrowed toward apical section, in apical section abruptly tapering, in lateral view moderately inflexed. Parameres each with conspicuous subbasal notch, bearing ventral, very finely striate lobe. Internal sac consisting of very dense scale-like and denticular structures, and with row of fairly small teeth.

E t y m o l o g y: The species epithet is a Latin adjective meaning angulate.

C o m p a r a t i v e n o t e s: The species shares with S. palawanum and S. inopportunum the narrow submesocoxal and submetacoxal areas and the very finely punctate body. It may be easily distinguished by the strigulate abdominal microsculpture and differs from these two species, as from other congeners, by the shape of the parameres. The aedeagal characters suggest placement within the S. pictum group.

Figures

Figs 137 - 141: Aedeagi of Scaphisoma; (137), S. scapulare nov. sp., apical part of median lobe with extruded internal sac, scale = 0.1 mm; (138, 139), S. tagalog nov. sp., aedeagus in dorsal and lateral views, scale = 0.1 mm; (140, 141), S. angulosum nov. sp., aedeagus in dorsal and lateral views, scale = 0.2 mm