Mecynotarsus iuvenis Kejval & Cz 2013, sp. nov.

Mecynotarsus iuvenis sp. nov.

(Figs 64–66)

Type locality. Australia, Western Australia, 12 km S of Kalumburu Mission, 14°25′S 126°38′E.

Type material. HOLOTYPE: 1 ♂, ‘ 14.25 S 126.38 E CALM Site 13/4 12 km S of Kalumburu Mission W.A. 7-11 June 1988, T.A. Weir [p] // at light closed forest // AUST. NAT. INS. COLL. [p; green label]’ (ANIC). PARATYPES: 5 ♀♀, same data as holotype (ANIC); 3 ♂♂ ‘ 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 spec. ZKDC); 2 ♂♂ 1 ♀, ‘ 17.25S 124.56E WA Lennard River, 29 April 1992 P. J. Gullan, at light [p] // AUST. NAT. INS. COLL. [p]’ (ANIC); 1 ♂, ‘ 13.45S 131.34E GPS Butterfly Gorge Nature Pk Douglas River NT 19 Jul. 1994, at light T. Weir,A. Roach [p] // AUST. NAT.INS. COLL. [p; green label]’ (ANIC); 6 ♂♂, ‘ AUSTRALIA, N. Territory Nitmiluk National Park, Edit Falls, 37 m alt, 14°10′S 132°06′E, 3.12.2008, St. Jakl leg. [p]’ (ZKDC, NMPC).

Description (holotype, male). Body length 2.0 mm. Body, legs, and antennae reddish brown.

Antero-lateral margins of frons simple. Gular rugules minute and scattered. Clypeal granules minute to indistinct. Setation of head rather evenly short and appressed, dense and finer medially on vertex, coarser to scaly around eyes and ventro-laterally. Antennae moderately long; antennomeres III–V at most nearly twice as long as wide, X about as long as wide; setation fine in apical half, and distinctly coarser to scaly in basal half.

Pronotum 1.6 times as long as wide, its lateral margins unevenly shaped, somewhat angled at widest point and then straight to slightly concave while narrowing towards base in dorsal view; posterior collar narrow but distinct, somewhat concealed by scaly setation. Pronotal horn moderately robust and wide, its posterior angles obsolete in dorsal view; horn margins armed with 4 lobules on each side; horn crest distinct, clearly raised, long and rather narrow, with coarse separate rugules on margins; submarginal rugules numerous, small and well-spaced; 5 small median rugules, mostly well-spaced, with some minute granules posteriorly. Setation whitish and reddish (dorsally), largely appressed and scaly, including dorsal surface of pronotal horn; scales on pronotal disc of two sizes / shapes, smaller and narrower or larger and wider, both widely rounded to truncate apically; antebasal paired setae short but distinct (somewhat thickened) laterally and absent medially, another tactile setae absent.

Elytra 1.7 times as long as wide; omoplates and postbasal impression absent. Setation scaly, whitish and pale reddish to brownish, somewhat mixed anteriorly and forming darker marking, evenly developed / ordered; scales distinctly elongate, rounded to subtruncate apically, very densely spaced but distinct; erect tactile setae absent.

Male characters. Sternum VII with small, sharply bordered median impression near base (Fig. 64). Tergum VIII and aedeagus as in Figs 65, 66; parameres strongly curved in apical third in lateral view.

Variation. Body length (♂ ♀) 1.8–2.2 mm. Pronotal horn with 4–5 lobules on each side; 5–8 median rugules. Dark markings of elytra in some specimens less distinct to absent.

Differential diagnosis. Mecynotarsus iuvenis sp. nov. is very close to M. albellus and also to M. ziczac, as suggested by the similar form of the parameres. It differs from both of these species by the presence of a small, sharply bordered median impression on male sternum VII, and the long, conspicuously raised setation of male tergum VIII; and from M. albellus by the evenly narrowing parameres that lack a small denticle / angulation on the lateral margins shortly before the apex.

Etymology. The species name is a Latin adjective, iuvenis (= young); named in reference to rather detailed differences distinguishing this species from M. ziczac and M. albellus.

Distribution. Australia: Northern Territory, Western Australia.

Remarks. Since females of Mecynotarsus iuvenis sp. nov. cannot really be distinguished from those of M. ziczac, only males of the former species are included in the types series for the localities that are shared between these two species (Jasper Gorge, Edit Falls; females are all tentatively identified as M. ziczac).