Probles (Euporizon) arkadyi Khalaim sp. nov.

Figs 1-6, 7-11

Comparison.

Probles arkadyi sp. nov. is easily distinguished from other Eastern Palaearctic species of the genus by its unusually small clypeus (Fig. 3) which is 0.6 times as broad as the face (shortest distance between eye margins). A similarly small clypeus is known in the Vietnamese species P. proshchalykini Khalaim, 2019, but the latter species has genae strongly swollen behind the eyes (in dorsal view), while in P. arkadyi sp. nov. the genae are distinctly constricted behind the eyes (Fig. 5). Probles arkadyi sp. nov. is also characterized by the long malar space and strongly tapered mandibles (Fig. 4).

Description.

Female. Body length 3.2 mm. Fore wing length 2.2 mm.

Head with gena distinctly and roundly constricted posterior to eyes (Fig. 5); gena in dorsal view 0.45 times as long as eye width. Clypeus unusually small, 2.1 times as broad as long and 0.6 times as broad as face (shortest distance between eye margins), smooth, with very fine and sparse punctures in upper half, separated from face by sharp furrow (Fig. 3). Mandible strongly constricted in basal 0.7; width of mandible at level of teeth about 0.4 times width at base; lower tooth almost 1.5 times longer than the upper (Fig. 4). Malar space about 1.1 times as long as basal mandibular width. Flagellum with 16-17 flagellomeres, filiform (Fig. 2); second flagellomere almost twice, flagellomeres 3-5 about 1.8 times, and subapical flagellomeres 1.2 times as long as broad; flagellomeres 4 to 6 (or more) bearing very small subapical finger-shaped structures on outer surface (these structures hardly discernible with a light microscope). Face with median swelling. Face, frons and vertex finely granulate, impunctate, dull. Gena shallowly granulate, impunctate, weakly shining. Occipital carina complete, evenly convex mediodorsally. Hypostomal carina absent (at least in lower part).

Mesosoma almost entirely granulate, impunctate and dull, except for mesopleuron, which is widely smooth and shining centrally above foveate groove (Fig. 6). Notaulus with irregular wrinkles (Fig. 5). Scutellum with lateral longitudinal carinae developed on anterior 0.3-0.4. Upper end of epicnemial carina curved abruptly forward to anterior margin of mesopleuron (Fig. 4). Foveate groove of mesopleuron long, oblique, almost straight, deep and moderately broad, with distinct transverse wrinkles, extending over anterior 0.6 of mesopleuron, almost reaching epicnemial carina anteriorly (Fig. 6). Propodeum with narrow to moderately broad basal area which is 2.5-3.5 times as long as broad and about half as long as apical area (Fig. 8). Propodeal spiracle separated from pleural carina by about 2.0 diameters of spiracle. Apical area slightly impressed along midline, narrowly rounded anteriorly (Fig. 8); apical longitudinal carinae complete and reaching transverse carina anteriorly (Fig. 8).

Fore wing (Fig. 7) with second recurrent vein (2m-cu) postfurcal. First abscissa of radius (Rs+2r) straight, somewhat longer than width of pterostigma. First and second sections of radius (Rs+2r and Rs) meeting at slightly acute angle. Intercubitus (2rs-m) slightly thickened, about as long as abscissa of cubitus between intercubitus and second recurrent vein (abscissa of M between 2rs-m and 2m-cu). Metacarpus (R1) short, not reaching tip of the wing. Second abscissa of postnervulus (Cu&2cu-a) present, thus brachial cell is closed posteriorly. Hind wing with nervellus (cu1&cu-a) weakly reclivous. Legs slender, tarsal claws not pectinate.

First tergite about 3.4 times as long as posteriorly broad, more or less trapeziform in central cross-section; lateral sides of petiole distinctly longitudinally striate before glymma (Fig. 10), petiole dorsally and postpetiole smooth; glymma deep, round, situated at posterior 0.55 of tergite and joining by thin and sharp furrow with ventral part of postpetiole (Fig. 10); in dorsal view, petiole with lateral margins subparallel, postpetiole distinctly widened anteriorly and almost twice broader than petiole (Fig. 9); upper margin of first tergite, in lateral view, nearly straight in anterior 0.7 and distinctly arcuate in posterior 0.3 (Fig. 10). Second tergite 1.5 times as long as anteriorly broad (Fig. 9). Thyridial depression deep and long, 2.5-3.0 times as long as broad, with posterior end rounded (Fig. 9). Ovipositor slender, weakly upcurved, with weak dorsal subapical depression (Fig. 11); sheath twice as long as first tergite (Fig. 1).

Head and mesosoma dark reddish brown (Fig. 6); lower 0.7 of clypeus, mouthparts and mandibles (teeth reddish black) yellow to brownish yellow. Antenna with scape and pedicel yellow ventrally and brownish dorsally; flagellum brown with basal flagellomeres yellowish brown. Tegula yellow-brown. Pterostigma brown. Legs brownish yellow; hind coxa slightly darkened with brown. First metasomal tergite dark brown. Metasoma posterior to first tergite predominantly brown, yellowish to pale brown ventrally (Fig. 1).

Male. Unknown.

Etymology.

The species is named in honour of the Russian entomologist, an expert in Mutillidae, Prof. Arkady S. Lelej (Vladivostok, Russia).

Material examined.

Holotype female (EUM), Japan, Hokkaido I., Sapporo, Hitsujigaoka, 43°00'27"N, 141°24'53"E, Malaise trap, 29.VI-6.VII.2010, coll. K. Konishi.

Paratypes. Japan: 1 female (EUM), same data as holotype, but 6-13.VII.2010 . 1 female (ZISP), same data, but 27.VI-4.VII.2011 . 1 female (ZISP), same data, but 4-11.VII.2011 . 1 female (EUM), same data, but 11-18.VII.2011 .

Distribution.

Japan (Hokkaido I.).