Chileanthicus quadrimaculatus Kejval 2009, comb. nov.

Chileanthicus quadrimaculatus (King, 1869) comb. nov.

(Figs 192–196, 219, 230)

Formicomus quadrimaculatus King, 1869: 7.

Type locality. Australia, South Australia, Gawler.

Redescription (male, South Australia, SAMA). Head and pronotum rufous brown, pronotum somewhat darkened antero-laterally; elytra dark brown, with two, rather vague, transverse, rufous bands (Fig. 192, 230) interrupted medially; legs, antennae and palpi rufous brown.

Head 1.2 times as long as wide, somewhat unevenly rounded posteriorly; tempora subparallel to distinctly narrowing posteriad; posterior temporal angles indistinct, rounded. Eyes small, convex. Dorsal surface slightly glossy, densely punctured (Fig. 192); punctation double and evenly developed. Setation pale to brownish, very fine, short, decumbent, with a few, quite inconspicuous erect setae. Antennae slender, at most slightly enlarged in terminal third; antennomere III 1.7 times as long as wide, as long as IV; X 1.7 times, XI about 2.4 times as long as wide.

Pronotum 1.2 times as long as wide, about as wide as head including eyes, somewhat unevenly rounded anteriorly; pronotal disc moderately convex, with slight impression/groove medially, close behind collar, its lateral margins forming rounded edge, lateral outlines nearly straightly narowing towards base in dorsal view. Dorsal surface slightly glossy; punctation and setation as on head.

Elytra 1.8 times as long as wide, nearly conjointly rounded apically. Surface slightly glossy, densely punctured (Fig. 192); punctation simple and fine. Setation mostly pale with brownish tinge and evenly directing posteriad, setae on transverse bands silvery and distinctly swirled; erect setae sparsely scattered, short and inconspicuous.

Metafemora unidentate (Fig. 193), subapical process comparatively small, somewhat obliquely projecting, pointed apically, facing inner side of tibia; mesotibiae with rather small denticle on inner side apically; metatibiae simple.

Abdominal sternum and tergum VII simple. Sternite VIII (Fig. 194); paired prongs strongly dilated and flattened distally, nearly quadrangular, and finely, sparsely setose. Tergite VIII with posterior margin moderately emarginate apically (Fig. 219).

Aedeagus (Figs 195, 196); apical portion of tegmen 1.4 times as long as basal-piece, with lateral (lateroventral) margins lobed, subapical lobes densely covered by minute spines on ventral (inner) side and apex of tegmen forming narrow and pointed process (Fig. 196); median lobe of aedeagus conspicuously bilobed apically.

Female. Externally differing from male by simple mesotibiae, lacking apical denticle.

Body length (♂ ♀). 3.4–4.5 mm.

Variation. Rather variable in colouration; head and pronotum may be rufous to dark brown, unicoloured; paler elytral bands in darker coloured specimens nearly indistinct, indicated only by silvery setation.

Type material. Syntypes: 1 ♂, [round orange label] // K 35021 [h] // Formicomus 4maculatus RLK Gawler [h] // HOLOTYPE [p; red label] (AMSA); 1 ♀: Gawler [h] // Co-type [p] // Formicomus quadrimaculatus King S. Australia Cotype 19049 [h; “Cotype” red] // S.Aust. Museum specimen [p; orange label) (SAMA).

Additional material. 1 ♂, 1 ♀, South Australia (SAMA); 3 ♀♀, Sas, Quorn, A. H. Elston leg. (AMSA, ZKDC); 1 ♂, Sas, Adelaide (AMSA); 1 ♂, 3 ♀♀, Sas, Kangaroo Island, A. H. Elston leg. (AMSA).

Differential diagnosis. C. quadrimaculatus differs from most species by the combination of unidentate metafemora, rather rounded lateral margins of the pronotal disc (no sharp edge), generally rather short body setation (erect setae inconspicuous), simply punctured elytra, with paler markings and setose bands, and double punctation of the head and pronotum. It shares these external characters and similar body form (nearly evenly rounded base of head) with C. volselifer sp. nov., but differs slightly by the form of the subapical process of the metafemora (cf. Figs 193, 213), and by all male characters (quite dissimilar morphology of the aedeagus, cf. Figs 194, 195 and 215, 216).

Distribution. Australia (South Australia).

Remarks. King (1869) described Formicomus quadrimaculatus from an unstated number of specimens collected by Masters and Kreusler in Gawler, South Australia. The records from Western Australia, New South Wales, and Murray Bridge in South Australia by Lea (1922) were found to be partly based on misidentifications, with these specimens belonging to C. melasomus or C. pumilio sp. nov. Identity of other specimens from the Lea collection (SAMA) is uncertain, as they are in poor condition or are single, somewhat aberrant females.