Cephennomicrus mediorugosus, Jałoszyński, 2018

Jałoszyński, Paweł, 2018, Revision of Cephennomicrus of Australia (Coleoptera, Staphylinidae, Scydmaeninae), Zootaxa 4422 (2), pp. 151-183 : 163-165

Cephennomicrus mediorugosus sp. n.

( Figs 42–47 , 54–57 , 123 )

Type material. Holotype: AUSTRALIA (QUEENSLAND): ♂, two labels: "11.45S 142.35E QLD / Heathlands 26Jan. - / 29Feb. 1992 P. Feehney / MALAISE #2 dump / open forest" [white, printed], " CEPHENNOMICRUS / mediorugosus m. / P. Jałoszyński, '18 / HOLOTYPUS" [red, printed] (ANIC). Paratypes (3 ♂♂): QUEENSLAND: 1 ♂, same data as for holotype; 1 ♂, same data except for 1021 Mar. 1992, closed scrub (Heath); 1 ♂, same data except for 22 Mar.–25 Apr. 1992, T. McLeod, heath (ANIC, cPJ).

Diagnosis. BL 0.80–0.83 mm; body stout, EI 1.13–1.19; antennomeres III–IX each as long as broad; antennal club dimerous, sharply delimited and strongly flattened; inner pair of pronotal antebasal pits not connected; frons in males modified, with a pair of impressions separated at middle by a long and narrow longitudinal carina that broadens anterad and posterad, and with a pair of short anterior sinuate ridges demarcating the impressions anterolaterally; aedeagus stout, drop-shaped, with complex endophallus containing median and lateral bunches of needle-like sclerites and a pair of subapical lateral subtriangular projections, subapical region of dorsal wall with paired setae.

Description. Body of male ( Fig. 42 ) stout, uniformly light brown; setae on head, pronotum and elytra very short, dense and recumbent, but discernible at magnification 40 ×. BL 0.80–0.83 mm (mean 0.81 mm).

Head ( Fig. 43 ) broadest at large, strongly convex and coarsely faceted eyes, HL 0.10 mm, HW 0.21–0.25 mm (mean 0.23 mm); frons and vertex modified, with a narrow and long median longitudinal carina separating a pair of lateral asetose impressions, carina broadens anterad and posterad, and each impression anterolaterally demarcated by a short sinuate ridge; supraantennal tubercles weakly elevated. Punctures fine and inconspicuous. Antennae short, with sharply delimited dimerous and strongly flattened club, AnL 0.35 mm, antennomeres I–II distinctly elongate, III–IX each as long as broad, X distinctly transverse, XI about as long as broad.

Pronotum subtrapezoidal, broadest near anterior fourth; PL 0.25–0.28 mm, PW 0.33–0.38 mm (mean 0.35 mm); anterior margin arcuate, posterior margin nearly straight, anterior corners broadly rounded, sides rounded in anterior third and nearly straight or indistinctly concave in posterior half, posterior corners strongly obtuse-angled and blunt; base with two lateral pairs of small but distinct pits, transverse groove absent; lateral pronotal carinae indistinctly serrate. Punctures on pronotal disc fine, inconspicuous.

Elytra oval, broadest distinctly anterior to middle; EL 0.45–0.48 mm (mean 0.46 mm), EW 0.40 mm, EI 1.13– 1.19; humeral calli distinct; apices separately rounded. Punctures similar to those on pronotal disc.

Legs moderately long and slender, unmodified.

Aedeagus ( Figs 44–47 , 54–57 ) stout; AeL 0.18 mm; median lobe in ventral view drop-shaped, endophallus complicated, with lateral bunches of long, needle-like sclerites, of which one pair is recurved and in most specimens ( Figs 44 , 54, 56, 57 ) directed laterad, but it can rotate and apices may be directed mesad ( Fig. 55 ); dorsal wall with paired setae in subapical region; each paramere with two apical and one subapical setae of equal length.

Female. Unknown.

Distribution ( Fig. 123 ). Queensland.

Etymology. The name mediorugosus refers to the median carina (or a wrinkle, ruga) on the frons in males.

Remarks. Although the body form of C. mediorugosus is unremarkable, the frons modification allows for easy identification of males. No other species has the frons impressed at each side of a narrow median longitudinal carina that broadens anterad and (more distinctly) posterad.

Figures

FIGURE 123. Distribution of Cephennomicrus in Australia; white circles denote nominal species, solid black circles denote undescribed species known from females only (distribution of undescribed species known from the same localities as nominal ones is omitted).

FIGURES 42–53. Cephennomicrus mediorugosus sp. n. (42–47) and C. wunundarranus sp. n. (48–53). Dorsal habitus (42, 48); head of male in dorsal view (43, 49); aedeagus in ventral (44, 46, 50, 52) and lateral (45, 47, 51, 53) views.

FIGURES 54–57. Variation in endophallic structures in Cephennomicrus mediorugosus sp. n.