Scydmaenus (Corbulifer) pseudorobustus Franz

Jałoszyński, Paweł, 2018, ' Monster Scydmaenus' of Australia: revision of subgenus Corbulifer Franz (Coleoptera: Staphylinidae: Scydmaeninae), Zootaxa 4472 (3), pp. 505-531 : 516-517

Scydmaenus (Corbulifer) pseudorobustus Franz

( Figs 30–32 , 58 , 69 , 70 )

Scydmaenus (Corbulifer) pseudorobustus Franz, 1975: 288 , figs 266–267.

Type material. HOLOTYPE: ( AUSTRALIA, QUEENSLAND): ♂, six labels: "Deviding {sic!} Range / Highway to Warwick / Queensld., Austr." [white, printed, with handwritten "Pa82" in blue ink on the reverse side], " Scydmaenus / ( Corbulifer ) / pseudorobustus / det.H.Franz" [white, handwritten and printed], " ♂ " {white, printed], " Typus " [red, handwritten], " SAMA Database / No. 25-037032" [white, printed], " SAMA Digital Image / 21.Aug 2013 " [green, printed and handwritten] ( SAM).

Additional material (2 exx.): QUEENSLAND: 12km SE of Rathdowney Mt Chinighee , 28°19'S, 152°58'E, 720 m, 17.12.1982, Monteith, Yeates & Thompson, QM Berlesate 496, rainforest litter (QM) ; NEW SOUTH WALES: 1 ♂, 28.29S 152.23E, Tooloom Scrub Floral Res., rest area, 755m, Beaury SF, 23km W of Urbenville , 16 Jun. 1993, D. S. Chandler, Berlesate ANIC 1648 , subtropical closed forest Dendrocnide excelsa (giant stinger) litter ( ANIC) .

Revised diagnosis. Male metatibia gradually and moderately broadened, indistinctly broader than metafemur, broadest distinctly distad middle, lateral (external) tibial margin bisinuate with a distinct submedian concavity, mesal tibial margin concave in proximal 1/5 and nearly evenly convex in distal 4/5, dorsolateral glandular 'pocket' present, with mesal margin bearing long setae; aedeagus in dorsal view broadest near base, with apical portion not delimited, apex divided into two very long and pointed lateral projections strongly bent dorsoproximad.

Redescription. Body of male ( Fig. 30 ) strongly convex, reddish brown, covered with setae slightly lighter than cuticle; BL 1.83–1.88 mm (mean 1.85 mm).

Head broadest at very small eyes, HL 0.35–0.38 mm (mean 0.37 mm), HW 0.40; tempora in lateral view as long as 5 × length of eye, only slightly convergent posterad and posteriorly bent mesad at a slightly obtuse angle. Punctures on frons and vertex very fine and shallow, inconspicuous; setae short, sparse and suberect. Antennae slender, AnL 0.95–1.03 mm (mean 0.99 mm), antennomeres I–VI each distinctly elongate, VII and VIII each about as long as broad, IX and X much larger than VIII, each slightly transverse, XI indistinctly longer than IX–X combined, nearly twice as long as broad.

Pronotum rounded, broadest slightly behind anterior third; PL 0.50–0.53 mm (mean 0.51 mm), PW 0.45–0.48 mm (mean 0.46 mm). Antebasal pits indistinct. Punctures on pronotal disc very fine and shallow, inconspicuous; setae short, sparse and suberect.

Elytra oval, broadest in front of middle; EL 0.98 mm, EW 0.73 mm, EI 1.34; apices separately rounded. Punctures relatively large and dense but very shallow, inconspicuous; setae longer and denser than those on pronotum, suberect to erect.

Metatibia ( Fig. 58 ) in dorsal view gradually and moderately broadened, broadest between middle and distal third, mesal margin concave in proximal 1/5, remaining portion nearly evenly convex, lateral (external) margin bisinuate with distinct submedian concavity; dorsolateral 'pocket' present, with mesal margin bearing long setae.

Aedeagus ( Figs 31–32 ) moderately slender; AeL 0.43 mm; in dorsal view median lobe broadest near base, relatively strongly narrowing distad with bisinuate lateral margins and broad, subtrapezoidal apical portion; apical projections conspicuously long, bent dorsoproximad at a sharp angle.

Female. Unknown.

Distribution. Queensland and New South Wales; central-eastern coast of Australia ( Fig. 70 ).

Remarks. Males of several species have the metatibiae modified in a similar way as those of S. pseudorobustus : S. eungellanus , S. gibraltar , S. kiwarrakianus and S. gushi (all described as new). All of them have the metatibiae gradually swollen and with a dorsolateral 'pocket' which divides the tibia into proximal and distal portions. In S. pseudorobustus the lateral (external) metatibial margin is very weekly concave at the 'pocket', in all remaining similar species the concavity is much deeper, so that the tibia appears recurved. Moreover, in S. pseudorobustus the proximal portion of metatibia is distinctly longer than the distal one, and consequently the tibia is broadest in its distal half. Only in males of S. eungellanus the proximal portion of metatibia is indistinctly longer than the distal portion, but adults of this species have the metatibiae of a different shape than those in S. pseudorobustus . Aedeagi of all these species differ markedly in the shape of the median lobe and apical structures.

Figures

FIGURE 70. Distribution of Corbulifer species.

FIGURES 30–32. Scydmaenus (Corbulifer) pseudorobustus Franz. Habitus of male (30), aedeagus in dorsal (31) and lateral (32) views.

FIGURES 55–65. Male metatibia in dorsal view. Scydmaenus tamborinensis Franz (55), S. monstrosetibialis sp. n. (56), S. bellenderanus sp. n. (57), S. pseudorobustus Franz (58), S. kiwarrakianus sp. n. (59), S. gushi sp. n. (60), S. gibraltar sp. n. (61), S. eungellanus sp. n., specimen from Mount William (62) and from Peases Lookout (63), S. fishermontanus sp. n. (64), S. super sp. n. (65).

FIGURES 66–69. Original labels of primary type specimens of previously described Corbulifer species. Scydmaenus tamborinensis tamborinensis Franz (66); Scydmaenus tamborinensis cunninghamensis Franz (67); Scydmaenus tamborinensis maipotonensis Franz (68); Scydmaenus pseudorobustus Franz (69).