Cephennomicrus bipunctatus, Jałoszyński, 2018

Jałoszyński, Paweł, 2018, Revision of Cephennomicrus of Australia (Coleoptera, Staphylinidae, Scydmaeninae), Zootaxa 4422 (2), pp. 151-183 : 174-175

Cephennomicrus bipunctatus sp. n.

( Figs 97–102 , 123 )

Type material. Holotype: AUSTRALIA (QUEENSLAND): ♂, three labels: " 12.44 S 143.14 E / 3km ENE of / Mt. Tozer QLD / 104 July 1986 / T.Weir", "Berlesate / ANIC 1052 / rainforest / litter" [white, printed], " CEPHENNOMICRUS / bipunctatus m. / P. Jałoszyński, '18 / HOLOTYPUS " [red, printed] ( ANIC). Paratype: 1 ♀, sama data as for holotype ( ANIC).

Diagnosis. BL 0.69–0.70 mm; body stout, EI 1.11–1.19; antennomeres III–IX each as long as broad, X transverse; antennal club dimerous and sharply delimited; inner pair of pronotal antebasal pits not connected, frons and vertex in males modified, frons between eyes with a pair of small circular pits, an arcuate groove laterad each pit, area between pits demarcated laterally by weakly elevated ridges and posteriorly by a faint subtriangular edge with a row of tiny setae, vertex with a submedian pair of irregularly microsculptured patches surrounded by smooth, asetose cuticle; aedeagus stout, with a pair of distal elongate sclerites, each serrate on lateral margin.

Description. Body of male ( Fig. 97 ) stout and strongly convex, uniformly reddish brown; setae on head, pronotum and elytra very short, dense and recumbent, discernible at magnification 80 ×. BL 0.69 mm.

Head ( Fig. 98 ) broadest at large, strongly convex and coarsely faceted eyes, HL 0.08 mm, HW 0.16 mm; frons and vertex in males modified, frons between eyes with a pair of small circular pits, an arcuate groove laterad each pit, area between pits demarcated laterally by weakly elevated ridges and posteriorly by a faint subtriangular edge with a row of tiny setae, vertex with a submedian pair of irregularly microsculptured patches surrounded by smooth, asetose cuticle; supraantennal tubercles weakly elevated. Punctures fine and inconspicuous. Antennae short, with sharply delimited dimerous club, AnL 0.33 mm, antennomeres I–II distinctly elongate, III–IX each about as long as broad, X distinctly transverse, XI about as long as broad.

Pronotum subtrapezoidal, broadest near anterior fourth; PL 0.23 mm, PW 0.30 mm; anterior and posterior margins weakly arcuate, anterior corners broadly rounded, sides strongly rounded in anterior third and indistinctly concave in posterior half, posterior corners distinctly obtuse-angled; 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 0.39 mm, EW 0.35 mm, EI 1.11; humeral calli distinct; apices separately rounded. Punctures similar to those on pronotal disc.

Legs moderately long and slender, unmodified.

Aedeagus ( Figs 99–102 ) stout; AeL 0.11 mm; median lobe in ventral view subtrapezoidal; endophallic structures weakly sclerotized except for a pair of conspicuous distal elongate projections, each with distinctly serrate lateral (external) margin; parameres not preserved.

Female. Differs from male in unmodified, evenly convex frons. BL 0.70 mm; HL 0.08 mm, HW 0.18 mm, AnL 0.30 mm; PL 0.23 mm, PW 0.30 mm; EL 0.40 mm, EW 0.34 mm, EI 1.19.

Distribution ( Fig. 123 ). Queensland.

Etymology. The name bipunctatus refers to a pair of pits on the frons in males.

Remarks. The body form of C. bipunctatus is unremarkable, but the uniquely modified frons in males and the very small aedeagus with distinctly serrate distal sclerites of endophallus can be used to distinguish this species from all its congeners. The frons and vertex modifications can be seen only by using a scanning electron microscope, except for the pair of pits, which is visible at high magnifications of a stereomicroscope.

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 91–102. Cephennomicrus longissimus sp. n. (91–96) and C. bipunctatus sp. n. (97–102). Dorsal habitus (91, 97); head of male in dorsal view (92, 98); aedeagus in ventral (93, 95, 99, 101) and lateral (94, 96, 100, 102) views.