Scaphisoma tridens, 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 : 1438

5.2.21.7. Scaphisoma tridens nov.sp. ( Figs 244-247 )

T y p e m a t e r i a l: Holotype 6: Philippines, Luzon: Lagunas, Mt. Makiling, abov. Mad Springs 400-700m, degrad. rainforest 19.-22.XI.1995, J. Kodada lgt. (MHNG). Paratype: with the same data as the holotype, 1 6 (MHNG).

D e s c r i p t i o n: Length 2.10 mm, width 1.52 mm. Head, thorax, most of elytra and abdomen uniformly reddish-brown, or hypomera somewhat lighter than pronotum, about apical fourth of elytra lighter, brown to yellowish, not clearly delimited. Appendages yellowish. Length/width ratio of antennomeres as: III 16/9: IV 53/8: V 75/6: VI 65/9: VII 75/13: VIII 55/11: IX 80/15: X 75/14: XI 95/15. Most other external characters as in S. tricoloratum. Elytra with sutural striae distinctly converging apically. Elytral punctation less dense, with puncture interval about as large as to twice as large than puncture diameters. Intercoxal process of sternite 1 with several fairly distinct punctures, remaining abdominal punctation, that along submetacoxal lines excepted, extremely fine, barely visible at 100 times magnification. Mesotarsomere 1 about as wide as apex of mesotibiae. Sternite 6 flat. Aedeagus ( Figs 244-247 ) 1.63-1.72 mm long. Apical process of median lobe with ventral branch short, inflexed, tapering apically, bent in dorsal view, with fairly acute tip. Dorsal branch of median lobe short, triangular in dorsal view, reaching beyond mid-length of ventral branch. Internal sac with curved proximal sclerites, filamentous basal structures joined to central complex of sclerites followed by rows of spine-like structures.

E t y m o l o g y: The species epithet is Latin and means three-toothed.

C o m p a r a t i v e n o t e s: The males of this species may be readily distinguished by their uniformly coloured pronotum in combination with the shape of the apical process of the median lobe of the aedeagus. Two female with the same locality data are tentatively associated, based on overall similarity.

Figures

Figs 242 - 246: Aedeagi of Scaphisoma in dorsal and lateral views, in lateral view without right paramere; (242, 243), S. tricoloripenne nov. sp.; (244, 245); S. tridens nov. sp.; (246), ditto, right paramere in ventral view. Scale = 0.3 mm.

Figs 247 - 250: Aedeagi of Scaphisoma; (247), S. tridens nov. sp., internal sac, scale = 0.1 mm; (248, 249), S. trifurcatum nov. sp., aedeagus in dorsal and lateral views, scale = 0.3 mm; (250), ditto, apical part of median lobe, oblique view, scale = 0.1 mm.