Scaphisoma frontale, Löbl, 2002

Löbl, I., 2002, New Species Of Scaphisoma Leach (Coleoptera: Staphylinidae: Scaphidiinae) From Mt. Wilhelm, Papua New Guinea, Acta Zoologica Academiae Scientiarum Hungaricae 48 (3), pp. 181-189 : 186-188

Scaphisoma frontale sp. n.

( Figs 7–8 )

Holotype male labelled: NewGuinea /NE/ Mt. Wilhelm 3600m Imbuka ridge 18.IX.1968 / No. NG-M. R.30/ leg. Dr. I. Loksa ( HNHM).

Paratypes: same data as holotype, 1 male ( MHNG) ; same data but No. NG-R. 31 leg. Dr. I. Loksa, 3 females ( HNHM, MHNG) ; Mt. Wilhelm 4–9.VIII.1969 / No. NGMt-B39/ leg. Dr. J. Balogh, 1 male ( MHNG) .

Description. Length 1.55–1.65 mm. Body black or very dark reddish-brown, elytra dark brown along apices, apical abdominal segments, femora and tibiae redish-brown. Tarsi and antennae lighter than tibiae. Length ratio of antennal segments as: III 5, IV 6, V 10, VI 11 VII 16, VIII 12, IX 14, X 13, XI 16 (holotype); segment III cylidrical, narrow, slightly narrower than segment IV, segment V about as wide as segment III, segment VI thickened apically, slightly wider than segment V; segment VII much wider than segment VI, segments VII and VIII each about 3 times as wide as long, segment XI oval, broad, hardly twice as long as wide. Eyes not conspicuously large, not entirely covering lateral parts of head. Pronotum moderately long, strongly narrowed anteriorly, with lateral contours arcuate. Lateral pronotal ridges not visible in dorsal view, or exposed at middle. Pronotal punctationsparse,extremelyfineandshallow.Exposedtipofscutellumminute.Elytradistinctlynarrowed toward base, widest posterior basal fifth, from widest point moderately narrowed toward apical third of lateral length, distinctly narrowed in apical third. Lateral elytral contours arcuate in apical third, straight in middle third. Sutural margin raised in apical half to apical two-thirds. Inner apical angle of elytra situated posterior line of outer apical angles; apical margins edentate, arcuate. Sutural striae shallow, almost parallel, extending anteriorly almost to line of scutellar tip, slightly curved outwards. Punctation of elytra similar to that of pronotum although slightly less fine. Metathoracic wings almost completely atrophied. Ventral side of thorax lacking microsculpture and very finely punctate.Mesepimeralridgeshorterthanintervaltomesocoxa.Metasternumshort,weaklyconvexin median part, lacking impressions. Mesocoxal lines parallel to coxae, indistinctly punctate. Mesocoxal areas narrow, 0.03 mm long, about as long as half of shortest interval to metacoxae. Metepisterna wide, strongly narrowed anteriorly, with inner margin almost straight, impressed below plane of metasternum. Abdomen very finely punctate and with punctulate microsculpture, latter absent from 1st exposed sternite. Metacoxal lines parallel, 0.03 mm long, with distinct marginal punctures. Tibiae straight, slender.

Male sexual characters. Frons with a large impression covered by a patch of adpressed, very dense, light pubescence. Protarsi weakly widened. Aedeagus ( Figs 7 and 8 ) 0.54–0.55 mm long, similar to that in S.fenestratum . Apical process of median lobe strongly inflexed laterally and less curved ventrally.

Comments. The pubescent frontal impression in males in S. frontale is a unique feature within the scaphidiines. In addition, this species may be distinguished from its allied by the comparatively short fourth antennal segment, in combination with the colour patter of the body. The aedeagus is similar to that in S. fenestratum but the apical process of the median lobe is less curved in S. frontale . The aedeagal characters indicate close relationships to S. fenetratum. These two species can be easily distinguished by the elytral colour pattern.

Figures

Figs 5–10. Aedeagus of Scaphisoma species: 5–6 = infirmum sp. n., scale bar = 0.1 mm; 7–8 = S. frontale sp. n., scale bar = 0.2 mm; 9–10 = S. medium sp. n., scale bar = 0.2 mm