Scaphisoma trifurcatum, 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 : 1439-1440

5.2.21.8. Scaphisoma trifurcatum nov.sp. ( Figs 42, 248-250 )

T y p e m a t e r i a l: Holotype 6: [Philippines] Yagumyum, Alt. ca. 1,400-1,600 m, Mt. Talinis, Negros Oriental, 28-29. V. 2013, J. Yasamako leg. (EUMJ). Paratypes: with the same data as the holotype, 1 6, 1♀ (EUMJ, MHNG); Negros Oriental, Mt. Talinis, Apolong trail, 500-1400 m, Valencia-Rancho, 30.V.2013, leg. J. Yamasako, 1♀ (MHNG).

D e s c r i p t i o n: Length 2.15-2.50 mm, width 1.60-1.78 mm. Head ochreous. Pronotum in male black along entire basal margin and with mesal triangular black spot, extended from basal margin up to anterior fourth of mesal length; most of pronotum ochreous, about as light as head. Pronotum in female black, with lateral ochreous spots not reaching basal or anterior margins. Elytra either ochreous on prevailing surface and black along base, on adsutural area, along sutural stria up to apical fourth, along lateral stria, on epipleuron, and with small black lateral spots, or black on prevailing surface and each with large ochreous spot; apical fifth to fourth yellowish or light brown. Hypomera ochreous. Ventral side of mesothorax and metathorax black. Abdomen with blackish sternite 1, following sternites becoming gradually lighter, apical abdominal segments and appendages yellowish. Pronotum and elytra not microsculptured and not iridescent. Antennae with relative length/width of antennomeres as: III 19/8: IV 54/9: V 85/8: VI 78/10: VII 77/15: VIII 65/10: IX 82/13: X 72/14: XI 80/15. Pronotum very finely and sparsely punctate, with lateral contours weakly rounded, lateral margin carinae exposed in dorsal view, lateral striae impunctate. Apex of scutellum exposed. Elytra with lateral margin carinae entirely and well visible in dorsal view, apical margins weakly rounded to truncate, inner apical angles rounded, not prominent, situated somewhat posterior level of outer angles; sutural margin flat in basal half, raised in posterior mid-length, sutural striae shallow, starting posterior level of scutellar tip, converging apically, very finely punctate; adsutural areas flat, densely and fairly coarsely punctate, punctures smaller than those on elytral disc; lateral striae punctate. Elytra with fairly coarse discal punctation, punctures rather well delimited, punctures intervals mostly as large to twice as large as puncture diameters. Hind wings fully developed. Hypomera and mesanepisterna smooth. Mesepimera slightly shorter than intervals to mesocoxae, about four times as long as wide. Median part of metaventrite convex, without impressions, flattened between metacoxae, with strigulate microsculpture, punctation evanescent. Lateral parts of metaventrite with microsculptured partly mesh-like, mostly strigulate, punctation very fine and sparse, evanescent between mesocoxae and metacoxae; antecoxal puncture rows distinct. Submesocoxal areas 0.03 mm, about as ninth of intervals to metacoxae, submesocoxal lines barely convex, distinctly punctate. Metanepisternum flat, weakly narrowed anteriad, inner margin straight, suture shallow. Protibiae straight, mesotibiae slightly bent, metatibiae slightly bent, thinner than mesotibae, somewhat thickened apically. Abdomen with strigulate microsculpture, almost entirely very finely punctate, punctures barely visible at 50 times magnification. Basomedian area of sternite 1 with two dense rows of distinct punctures; submetacoxal areas 0.06 mm, about as fourth of interval to apical margin, submetacoxal lines convex, densely punctate.

M a l e: Prevailing pronotal colour ochreous. Tarsomeres 1 of prolegs and mesolegs widened, somewhat narrower than apices of tibiae; tarsomeres 2 slightly narrower, tarsomeres 3 much narrower than tarsomeres 1. Sternite 6 flattened. Aedeagus ( Figs 248- 250 ) 1.76-1.82 mm long, asymmetrical, with basal bulb very large, moderately sclerotized, overlapping apically basal part of apical process, and with large ventral ridge. Ventral branch of apical process of median lobe long, strongly inflexed, narrowed posterior mid-length and with blunt tip in dorsal view, almost evenly wide and with obliquely truncate apex in lateral view. Dorsal branch of apical process fairly long, narrowed apically, reaching posterior level mid-length of ventral branch. Parameres with robust ventral apophysis and large, overlapping dorsal lobes. Internal sac with trifid curved basal tooth and complex sclerites and rods in basal and middle parts followed by dense rows of spines.

F e m a l e: Prevailing pronotal colour black, ochreous surface limited to two lateral spots. Apical margins of elytra as in male.

E t y m o l o g y: The species epithet is a Latin adjective, meaning three-forked. Co mpara tive note s: The species resembles in most diagnostic characters, in particular by its colour pattern, to S. tricoloripenne and S. trimaculatum. The females of S. trifurcatum may be distinguished by the not denticulate inner apical angles of the elytra and thus unlike those in twese two species. The males may be easily distinguished by the unique shape of the apical process of the median lobe.

Figures

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.