Mecynotarsus dearmatus Kejval & Cz 2013, sp. nov.

Mecynotarsus dearmatus sp. nov.

(Figs 42, 43)

Type locality. Australia, Western Australia, Drysdale River, 15°02′S 126°55′E.

Type material. HOLOTYPE: ♂, ‘ 15.02S 126.55E Drysdale River, W.A. 3–8 Aug. 1975 I.F.B. Common and M.S.Upton [p] // ANIC Specimen [p; green label]’ (ANIC). PARATYPES: 7♂♂ 1♀, same data as holotype (ANIC, 1 spec. ZKDC);

1 ♂, ‘ 16.02S 130.48E NT Jasper Gorge GPS 15 Oct. 2000 T.Weir & D.Yeates at light [p] // ANIC Specimen [p; green label]’ (ANIC); 1 ♂, ‘ 17.25S 124.56E WA Lennard River 29 April 1992 P.J.Gullan at light [p] // AUST. NAT. INS. COLL. [p; green label]’ (ANIC); 2 ♂♂ 1 ♀, ‘ Bessie Spring 16.40S 135.51E 8km ESE of Cape Crawford, NT. 26 Oct. 1975 M.S.Upton [p] // AUST. NAT. INS. COLL. [p; green label]’ (ANIC).

Description (holotype, male). Body length 2.6 mm. Reddish to reddish brown, head somewhat darker, nearly brown black dorsally.

Antero-lateral margins of frons distinctly lobed near insertion of antennae (margin of lobe somewhat angled, smooth and glossy). Gular rugules rather coarse, especially anteriorly and here ordered as in Fig. 138. Clypeal granules indistinct. Setation of head vertex mostly fine, appressed, with long, more erect setae in median line and basally, and coarser to scaly around eyes and ventro-laterally. Antennae conspicuously long; antennomeres V–VII most elongate, about 2.2 times as long as wide, antennomere II at most slightly shorter than III, antennomere X 1.8 times as long as wide; basal 4–5 antennomeres with coarser to scaly setation.

Pronotum 1.6 times as long as wide, its lateral margins somewhat unevenly convex in dorsal view; posterior collar distinct; surface of pronotal disc with numerous scattered granules (sparser, coarser and pointed dorso-laterally), posterior collar medially with pair of similar minute granules. Pronotal horn rather robust, moderately wide, subtriangular, its posterior angles moderately indicated in dorsal view; horn margins armed with 4 rather long, apically rounded lobules on each side, apical lobule simple, widely rounded; horn crest distinct, rather wide, with coarse, separate rugules on margins; submarginal rugules small, partly serial; about 7 median rugules, mostly rather coarse and well-spaced, and some smaller granules posteriorly. Setation whitish, scaly, mostly appressed to subdecumbent, strongly reduced on pronotal horn dorsally; scales on pronotal disc of two sizes, smaller scales quite appressed, larger scales subdecumbent, elongate to linear, truncate apically; antebasal paired setae present medially and difficult to recognize laterally owing to presence of numerous additional tactile setae.

Elytra 1.7 times as long as wide; omoplates and postbasal impression absent. Setation whitish, pale reddish and reddish brown, somewhat mixed and also forming vague darker markings, scaly, uniform, appressed and evenly ordered; scales longitudinally oval to linear, rounded to subtruncate apically, very dense (surface barely visible); several tactile setae present at base.

Male characters. Sternum VII moderately produced and rounded postero-medially. Tergum VIII and aedeagus as in Figs 42, 43.

Variation. Body length (♂ ♀) 2.2–2.6 mm; pronotal horn with 3–4 lobules on each side; 6–11 median rugules; dark markings on elytra distinct to feebly indicated.

Differential diagnosis. Mecynotarsus dearmatus sp. nov. resembles M. granulatus sp. nov. and M. imitator sp. nov. in having uniformly short and appressed scaly setation on the elytra (scattered tactile setae absent), however it differs from both species by the distinctly lobed antero-lateral margins of the frons and by the shape of the parameres of the aedeagus.

Etymology. The species name is the Latin adjective, dearmatus, -a, um (= disarmed); named in reference to the shorter projections of the frontal margins.

Distribution. Australia: Northern Territory, Western Australia.