Scydmaenus (Corbulifer) eungellanus, Jałoszyński, 2018

Jałoszyński, Paweł, 2018, ' Monster Scydmaenus' of Australia: revision of subgenus Corbulifer Franz (Coleoptera: Staphylinidae: Scydmaeninae), Zootaxa 4472 (3), pp. 505-531 : 523-525

Scydmaenus (Corbulifer) eungellanus sp. n.

( Figs 42–47 , 62–63 , 70 )

Type material. HOLOTYPE: ( AUSTRALIA, QUEENSLAND): ♂, two labels: " QUEENSLAND (MEQ) / Eungella N.P., Mount / William, 19 Apr 1979 / G.B. Monteith " [white, printed], "Q.M. BERLESATE NO. 42 / 21.02S 148.36E / Rainforest, 1100m / Sieved litter" [white, printed] (QM) . PARATYPES (4 exx.): QUEENSLAND: 2 ♀♀, same data as for holotype ; 2 ♂♂, two labels: " C.Qld: 21°07' Sx 148°31'E / Pease's Lkt {i.e., Lookout}, Eungella / 17 Nov 92 -mid Apr 1993 / D.Cook & G.B.Monteith, 900m / RF Intercept & Pitfalls" [white, printed] (QM, cPJ).

Diagnosis. Male metatibia gradually and moderately broadened, slightly broader than metafemur, broadest near distal third, mesal tibial margin slightly concave in proximal third, convex at middle and nearly straight in distal third, lateral (external) tibial margin convex both in proximal and distal halves but with a short and indistinctly concave portion near distal 1/4–1/5, with a distinct submedian concavity, dorsolateral glandular 'pocket' present, with its mesal margin bearing long but relatively sparse setae, dorsomedian portion of the 'pocket' developed as a large and nearly circular pit; aedeagus in dorsal view nearly parallel-sided in proximal 3/4, with indistinct sub-basal constriction, apical portion nearly parallel-sided; apical projections very long and bent dorsoproximad at a sharp angle.

Description. Body of male ( Figs 42 , 45 ) strongly convex, moderately dark brown, covered with setae slightly lighter than cuticle; BL 1.98–2.05 mm (mean 2.02 mm).

Head broadest at small eyes, HL 0.40–0.43 mm (mean 0.41 mm), HW 0.40–0.41 mm (mean 0.40 mm); tempora in lateral view about twice as long as eyes, 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 1.03–1.05 mm (mean 1.04 mm), antennomeres I–VI each distinctly elongate, VII and VIII each about as long as broad, IX and X much larger than VIII, IX about as long as broad, X slightly transverse, XI indistinctly shorter than IX–X combined, about 1.8 × as long as broad.

Pronotum rounded, broadest slightly behind anterior third; PL 0.58 mm, PW 0.50–0.55 mm (mean 0.53 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 1.00– 1.05 mm (mean 1.03 mm), EW 0.83–0.90 mm (mean 0.84 mm), EI 1.17–1.27; apices separately rounded. Punctures small and superficial, barely noticeable; setae longer and denser than those on pronotum, suberect to erect.

Metatibia ( Figs 62–63 ) in dorsal view gradually and moderately broadened, broadest near distal third, mesal margin concave in proximal third, convex at middle and nearly straight in distal third, lateral (external) margin convex both in proximal and distal halves but with a short indistinctly concave portion near distal 1/4–1/5, with a deep concavity near middle; dorsolateral 'pocket' present, with its mesal margin bearing long but sparse and relatively inconspicuous setae, dorsomedian portion of 'pocket' developed as a deep and nearly circular pit.

Aedeagus ( Figs 43–44 , 46–47 ) relatively slender; AeL 0.40 mm; in dorsal view median lobe similarly broad near base and near middle, with lateral margins only indistinctly concave in between, gradually and weakly narrowing distad to form an elongate subrectangular apical portion, with apical projections long and bent dorsoproximad at a sharp angle. A slight variability in aedeagal structures was found between specimens from Mount William ( Figs 43–44 ) and those from the Peases Lookout ( Figs 46–47 ); males from the latter site have the apical projections more strongly bent.

Female. Similar to male, but with unmodified metatibiae and much smaller eyes; length of temple equals 5–5.5 lengths of eye in lateral view. BL 2.05 mm; HL 0.40 mm, HW 0.43 mm, AnL 0.98 mm; PL 0.55–0.58 mm, PW 0.53–0.55 mm; EL 1.08–1.10 mm, EW 0.85–0.88 mm, EI 1.26.

Distribution. Queensland; north-eastern coast of Australia ( Fig. 70 ).

Etymology. Locotypical, after Eungella National Park.

Remarks. Males of Scydmaenus eungellanus can be easily distinguished from congeners with weakly broadened metatibiae on the basis of a nearly circular impression at base of the dorsolateral metatibial 'pocket', well-visible in dorsal view.

Differences in the aedeagi were found between specimens collected in two localities within the Eungella National Park ( Figs 43–44 vs. 46–47); some males have the apical projections bent more strongly than others. However, proportions of body parts ( Figs 42 , 45 ) and the metatibial modifications ( Figs 62–63 ) do not differ, and these specimens are interpreted here as belonging in the same species.

Figures

FIGURE 70. Distribution of Corbulifer species.

FIGURES 42–44. Scydmaenus (Corbulifer) eungellanus sp. n., specimen from Mount William. Habitus of male (42), aedeagus in dorsal (43) and lateral (44) views.

FIGURES 45–47. Scydmaenus (Corbulifer) eungellanus sp. n., specimen from Peases Lookout. Habitus of male (45), aedeagus in dorsal (46) and lateral (47) 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).