Euconnus (Glabriconnus) aterrimus Franz

Jałoszyński, Paweł, 2016, Taxonomy of ' Euconnus complex'. Part VII. Glabriconnus, a new subgenus of Euconnus from Madagascar (Coleoptera, Staphylinidae, Scydmaeninae), Zootaxa 4084 (4) : -

Euconnus (Glabriconnus) aterrimus Franz

( Figs 34–38 )

Euconnus (s. str.) aterrimus Franz, 1986: 214 , fig. 187.

Type material. Holotype (MADAGASCAR): ♀, four labels: "Massif de l'An- / karatra,Madagaskar / lg.H.Franz 1969" with "Mg 7" on the reverse side [white, printed; reverse handwritten], "♀" [white, printed], " Euconnus / (s. str.) / aterrimus m. / det. H. Franz" [yellowish, handwritten and printed], "Typus" [red, handwritten], " EUCONNUS / (GLABRICONNUS) / aterrimus Franz, 1986 / det. P. Jałoszyński, 2015" [white, printed] (NHMW).

Diagnosis. Small adults, BL about 2 mm; frons lacking longitudinal carinae; pronotum with one very faint hypomeral groove at each side; elytra oval, similarly narrowing posteriorly and anteriorly.

Description. Body of female ( Figs 34–35 ) strongly convex, elongate with deep constriction between head and pronotum and between pronotum and elytra, appendages long; BL 2.08 mm; cuticle glossy and slightly opalescent, very dark brown, only tarsi lighter; setae yellowish, bristles nearly as dark as cuticle.

Head ( Figs 36–37 ) in dorsal view suboval, broadest at eyes, HL 0.38 mm, HW 0.40 mm; vertex and frons confluent, lacking longitudinal carinae; supraantennal tubercles weakly raised but distinct; tempora about twice as long as eyes in dorsal view; eyes moderately large and moderately convex, coarsely faceted; head in lateral view ( Fig 37 ) weakly flattened and with vertex slightly bulging posterodorsally. Punctures on vertex and frons very fine and sparse, inconspicuous; setae on vertex and posterior portion of frons indiscernible, only frons between supraantennal tubercles with several moderately long and suberect setae; genae and postgeneae, but not tempora, with thick bristles. Antennae moderately long, AnL 0.95 mm; antennomeres I–II strongly elongate, III–IV weakly elongate, V–VII distinctly elongate, VIII–X distinctly transverse, XI slightly broader than X, nearly as long as IX– X together, about 1.5× as long as broad, with subconical and indistinctly pointed apex.

Pronotum in dorsal view ( Fig. 34 ) bell-shaped, broadest distinctly in anterior third, PL 0.53 mm, PW 0.53 mm; anterior margin nearly straight, anterior corners weakly marked, obtuse-angled and blunt; lateral margins strongly rounded in anterior half and concave just in front of posterior corners, which are nearly right-angled and blunt; posterior margin slightly bisinuate; base with one distinct pair of deep lateral setiferous pits; sublateral carinae absent; each side of pronotum with one very faint hypomeral groove extending along posterior third and not visible in dorsal view. Punctures on pronotal disc not visible at magnifications up to 80×; vestiture composed of very sparse but distinct, moderately long and suberect setae distributed on pronotal disc and dense bristles along its anterior margin and below lateral hypomeral grooves ( Fig. 37 ).

Elytra ( Figs 34–35 ) oval, broadest slightly in front of middle, EL 1.18 mm, EW 0.90 mm, EI 1.31; elytral base as broad as pronotal base, lacking impressions and humeral calli. Punctures on elytral disc as fine as those on pronotum; setae very sparse and short, nearly recumbent. Hind wings absent

Legs ( Figs 34–35 ) moderately long and slender; unmodified.

Male. Unknown.

Distribution. Central Madagascar ( Fig. 38 ).

Remarks. Despite extensive collecting efforts in central part of Madagascar that yielded several thousand Scydmaeninae , no additional specimens of this interesting species have been found. Although females of Euconnus are often difficult to identify, this particular species clearly differs from all Madagascan congeners and it can be identified on the basis of subgeneric diagnostic characters, body shape, measurements and proportions of body parts and very dark pigmentation.

Figures

FIGURE 38. Distribution of Euconnus (Glabriconnus) spp. in Madagascar.

FIGURES 34 – 37. Euconnus (Glabriconnus) aterrimus Franz, female. Dorsal (34) and lateral (35) habitus; head in dorsal view (36); head and prothorax in lateral view (arrow showing faint hypomeral groove) (37).