Scaphisoma donati, Löbl, 2022

Löbl, Ivan, 2022, Supplement to the knowledge of the Scaphidiinae (Coleoptera: Staphylinidae) of the Moluccas, Revue suisse de Zoologie 129 (1), pp. 103-118 : 114

Scaphisoma donati sp. nov.

Figs 20-23

Material examined: Holotype; MHNG; male; MALUC: Tanimbar Isl. , Sangliat Krawai E Yamdena , 19.IX.81 D. Agosti F911120 .

Etymology: The species is named in honour of its collector, Donat Agosti (Bern, Switzerland).

Diagnosis: The species is defined by the following characters in combination: Body-length nearly 2 mm, body dark reddish-brown, not microsculptured; elytra with sutural striae parallel, basal striae entire, joined to lateral striae; mesepimeron shorter than interval between its tip and mesocoxa; metaventrite distinctly punctate on transverse area anterior of metacoxal process, lacking fovea-like impressions; submesocoxal and submetacoxal areas very narrow, with parallel lines; aedeagus as Figs 20-23 , strongly asymmetrical, parameres lobed, overlapping apex of median lobe, internal sac strongly sclerotized.

Description: Length 1.94 mm, width 1.33 mm. Head and most of body nearly evenly dark reddish-brown. Apex of abdomen and appendages lighter. Antennomere II about four times as long as antennomere III. Length/ width ratios of antennomeres as: III 9/10: IV 38/8: V 56/9: VI 52/8: VII 56/13: VIII 44/8: IX 57/15: X 52/14: XI 58/15. Pronotum and elytra not microsculptured. Pronotum with lateral margins rounded, lateral margin carinae not visible in dorsal view, discal punctation dense and very fine, consisting of poorly delimited punctures. Minute point of scutellum exposed. Elytra moderately narrowed apically, lateral margin rounded, lateral margin carina clearly exposed in dorsal view only in basal third, inner apical angle about in level with outer apical angle, sutural margin not raised, adsutural area flat, not narrowed apically, with very fine puncture row; sutural striae curved at base and extended laterally to form basal striae joined to lateral striae, discal punctation irregular, fine, punctures not well delimited, puncture intervals mostly about twice to five times as large as puncture diameters. Hind winds reduced. Exposed tergites very finely punctate, not microsculptured. Hypomeron smooth. Mesepimeron about four times as long as wide, distinctly shorter than interval between its tip and mesocoxa. Metaventrite short, not microsculptured, slightly convex in middle. Mesocoxal process concealed with mesoventrite. Centre of metaventrite impunctate, fairly coarse punctures present on transverse area anterior metacoxal process, fovea-like impressions absent. Lateral parts of metaventrite very finely and sparsely punctate, punctures on lateral areas hardly visible, antecoxal puncture rows absent. Submesocoxal lines parallel, fairly coarsely punctured; submesocoxal area about 0.02 mm long, as tenth of shortest distance to metacoxa. Metanepiternum narrowed anteriad. Ventrite I with punctation very fine, similar to lateral parts of metaventrite; submetaxocal lines parallel, margined with coarse punctures; submetacoxal areas hardly 0.02 mm, about as tenth of shortest distance to apical margin.

Male characters: Ventrite VI with mesal process triangular, about 0.15 mm long. Protarsomeres and mesotarsomeres I to III distinctly widened, with tenant setae, protarsomeres I narrower than apices of protibiae. Aedeagus ( Figs 20-23 ) 1.25 mm long, strongly sclerotized and strongly asymmetrical. Apical process of median lobe slightly inflexed, obliquely truncate at apex. Left paramere extended posterior of right paramere and overlapping most of apical process. Internal sac with robust, strongly sclerotized and irregularly narrowed rod.

Habitat: Kanary evergreen primary forest on limestone, 50 m, thick leaf litter with heavy mycorrhiza.

Distribution: Indonesia: Moluccas, Yamdena Island.

Remarks: This is a member of the S. sublimbatum group. It may be easily distinguished from the other five members of the group by the elytra lacking spots, the metaventrite lacking mesal stria and fovea-like impressions, the antennomeres XI about as large as the antennomeres IX, and the basal striae of the elytra entire, joined to the lateral striae, in combination. The aedeagal characters suggest close relationships to S. quadripunctatum (Pic, 1956) , the shape of the truncate tip of the apical process of the median lobe is unique in the new species. Its reduced hind wings suggest narrow endemism.

Figures

Figs 19-22. Baeocera punctiventris sp. nov. (19) Aedeagus in lateral view. Figs 20-22. Scaphisoma donati sp. nov. (20, 21) Aedeagus in dorsal and lateral views, scale bars 0.2 mm. (22) Median lobe with left paramere, without internal sac.

Figs 23-29. Scaphisoma donati sp. nov. (23) Parameres in ventral view, scale bar = 0.2 mm. Figs 24-27. Scaphobaeocera plana sp. nov. (24, 25) Aedeagus in dorsal and lateral views, scale = 0.1 mm. (26) Paramere in ventral view, scale = 0.05 mm. (27) Apical part of median lobe, in lateral view, scale = 0.05 mm. Figs 28, 29. Scaphoxium lobatum sp. nov. (28) Aedeagus in ventral view, scale = 0.1 mm. (29) Apex of median lobe with extruded internal sac and right paramere, in dorsal view, scale = 0.05 mm.