Scaphisoma semibreve, Löbl, 2014

Löbl, Ivan, 2014, On the Scaphidiinae (Coleoptera, Staphylinidae) of the Moluccas, Mitteilungen Der Schweizerischen Entomologischen Gesellschaft 87, pp. 49-60 : 57-59

Scaphisoma semibreve sp. n.

( Figs 14. 15 )

Holotype ♂ labelled: INDO: Maluc F911217 Tanimbar Isl: Yamdena leaf litt Agosti 14.9.91 ( MHNG).

Paratype ♀: INDO: Maluc F911121 Tanimbar Isl. Yamdena Sangliat Kramain Agosti 14.9.91 (11) ( MHNG) .

Description. Length 1.50 mm, width 1.02 mm. Head and most of body dark reddish-brown, apices of elytra lighter, apical half of sternite 1 and sternites 2 and 3 darkened, almost black, femora reddish-brown. Tibiae, tarsi and antennae lighter than femora, almost yellowish. Dorsum of body lacking microsculpture. Antennae long, length/width ration of antennomeres similar as in S. apterum . Pronotum very finely punctate, with lateral margins of evenly rounded, lateral margin carina hardly visible in dorsal view. Scutellum concealed. Elytra with lateral margin carinae hardly visible in dorsal view, apical margins slightly rounded, inner apical angle situated posterior to level of outer angles, suturai margin not raised, suturai striae shallow, parallel, at base curved, not extending laterad pronotal lobe, adsutural areas flat. Elytral punctation dense, very fine, punctures larger than those on pronotum. Metathoracic wings reduced. Hypomera smooth. Mesepimeron about 1.5 times as long as interval to mesocoxa. Metaventrite very finely punctate, not microsculptured, with median part flat. Submesocoxal area 0.02-0.03 mm, about one third to half of interval to metacoxa, submesocoxal lines parallel, with fine marginal punc- tures. Metanepisternum flat, strongly narrowed anterad, inner margin oblique, rounded near angles, impressed below margin of metaventrite. Abdomen very finely punctate, lacking obvious microsculpture. Submetacoxal areas 0.02 mm, submetacoxal lines parallel, with coarse margin punctures. Tibiae straight.

Male sexual characters. Protarsomeres 1 to 3 weakly widened. Aedeagus ( Figs 14. 15 ) 0.75 mm long. Median lobe asymmetrical, with long, sclerotized, almost anchor-like apophysis on ventral side of basal bulb. Ventral process small, not prominent. Left side of apical process strongly sclerotized, right side weakly sclerotized. Apical process strongly narrowed apically, sinuate, tapering. Paramères with broad bases, curved and narrowed toward mid-third, middle third almost evenly narrow in lateral view, abruptly broadened to form weakly sclerotized apical lobes, each with dense patch of pores and tubules. Internal sac membranous in proximal part, with two long rows of robust teeth.

Distribution. Moluccas, Tanimbar group: Yamdena Island.

Etymology. Latin adjective, referring to the comparatively short metaventrite.

Comments. The female paratype is teneral and lighter than the holotype. The species is very similar to S. apterum , although its elytral punctation is not so fine. These two species share an anchor-like apophysis on the ventral side of the basal bulb of the aedeagus, unknown in remaining congeners. The two species may be easily distinguished by the shape of the paramères and of the teeth-like sclerites of the internal sac.

Figures

Figs 14-15. Scaphisoma semibreve sp. n.. aedeagus in dorsal view (14), same, in lateral view (15); scale bar 0.2 mm.