Scaphisoma nanellum, 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 : 1360-1361

5.2.4.4. Scaphisoma nanellum nov.sp. ( Figs 63, 64 )

T y p e m a t e r i a l: Holotype 6: Tarragona, Leyte I., Philippine Isls. VIII-IX: 1945 / Col. & pres. By C.L.Remington / On polypore fungi (FMNH). Paratype: with the same data as the holotype, 1♀ (MHNG).

D e s c r i p t i o n: Length 0.84-0.91 mm, width 0.62-0.65 mm. Head and dorsum of body dark brown, ventral side of body lighter, reddish-brown, appendages light, almost yellowish. Pronotum and elytra not microsculptured and not iridescent. Length/width ratio of antennomeres as: III 5/5: IV 10/5: V 16/6: VI 16/6: VII 25/8: VIII 15/7: IX 27/12: X 22/12: XI 37/11. Pronotum with lateral margins evenly rounded, lateral margin carinae not visible in dorsal view, lateral striae impunctate, punctation dense, very fine, hardly visible at 50 times magnification. Exposed tip of scutellum minute. Elytra convex, with lateral margin carinae impunctate, visible in dorsal view, apical margins rounded, inner apical angles not prominent, situated slightly posterior level of outer angles; sutural margin slightly raised, sutural striae deep, parallel from level of scutellar tip to apices, appearing impunctate, bent at base, basal striae absent; adsutural areas narrow, flat, with hardly visible puncture row. Elytral disc with punctation sparse and about as fine as that on pronotum. Hind wings fully developed. Hypomera, mesanepisterna, metaventrite and abdomen without obvious microsculpture. Mesepimera slightly longer than halves of intervals to mesocoxae and almost twice as long as wide. Metaventrite extremely finely punctate. Median part of metaventrite flattened, lacking impressions or stria; antecoxal puncture rows absent. Submesocoxal areas 0.03 mm, almost as third of intervals to metacoxae, submesocoxal lines convex, distinctly punctate. Metanepisternum flat, wide, narrowed anteriad, inner margin almost straight, suture deep. Tibiae straight. Abdomen with punctation very fine and sparse, hardly visible; submetacoxal areas hardly 0.02 mm, about as fourth of intervals to apical margin of sternite, submetacoxal lines hardly convex, with comparatively coarse marginal punctures.

M a l e: Protarsomeres 1 to 3 weakly widened. Aedeagus ( Figs 63, 64 ) 0.35 mm long, symmetrical, weakly sclerotized. Median lobe with apical process notably shorter than narrow basal bulb, narrowed toward tip, obliquely inflexed in apical third; articular process prominent, tip acute. Parameres widened toward mid-length and strongly narrowed apically in dorsal view, gradually narrowed from middle toward apices in lateral view. Internal sac with flagellum and subapical vesicle bearing minute spine-like structures.

Etymology: The species epithet is an adjective, derived from Greek nanos meaning dwarf.

Comparative notes: This species may be readily distinguished from S. blefusca and S. liliput by the shape of the parameres. In addition, it differs distinctly from the allied species by the length ration of the antennomeres III to VI. See also notes under S. ilonggo.

Figures

Figs 58 - 64: Scaphisoma; (58), S. ilonggo nov. sp., aedeagus in lateral view, internal sac extruded; (59, 60), S. liliput nov. sp., aedeagus in lateral and dorsal views, internal sac extruded; (61), ditto, parameres in ventral view; (62), ditto, paramere in lateral view; (63, 64), S. nanellum nov. sp., aedeagus in dorsal and lateral views. Scale = 0.1 mm.