Peucobius shimizui Khalaim, 2023

Khalaim, Andrey I., Ruiz-Cancino, Enrique & Coronado-Blanco, Juana Maria, 2023, Taxonomy of the genus Peucobius Townes (Hymenoptera, Ichneumonidae, Sisyrostolinae), Journal of Hymenoptera Research 95, pp. 245-260 : 245

Peucobius shimizui Khalaim sp. nov.

Figs 12-17 , 18-20

Remarks.

The species was collected on Pinus densiflora in spring period together with a large quantity of individuals of Gelanes spp. ( Tersilochinae ).

Comparison.

This species differs from the three Nearctic species in having a longer metacarpus (R1) of the fore wing (Fig. 18 ) (ending just behind the radial cell in all other species, see Figs 1 , 2 , 9 ).

Description.

Female. Body length 2.8 mm. Fore wing length 2.6 mm.

Head with gena strongly rounded posterior to eyes (Fig. 14 ); gena in dorsal view 0.65 times as long as eye width. Clypeus 3.3 times as broad as long (Fig. 15 ), very weakly convex, smooth, with fine punctures in upper 0.4, with a row of long fine setae on lower margin. Mouthparts short; maxillary palp with 5 palpomeres, palpomeres 4 and 5 short, distinctly shorter than palpomeres 2 and 3; labial palp with 4 short palpomeres. Mandible with lower tooth distinctly broader and somewhat longer than upper (Fig. 15 ); both teeth in holotype and paratype very obtuse (rounded apically), possibly abraded. Malar space as long as basal mandibular width, with broad scabrous area between eye and mandibular base. Flagellum with 15 flagellomeres, filiform; flagellomeres 2 to 4 about 2.6 times and subapical flagellomeres 1.1-1.3 times as long as broad. Face with weak median swelling and small median tubercle in upper part of this swelling, without longitudinal furrow; face with very fine punctures on smooth background, smooth and impunctate centrally on median swelling. Frons without ridge between antennal sockets, with very fine (partly indistinct) punctures on smooth background, laterally slightly scabrous. Vertex and gena polished, with very fine setiferous punctures. Occipital carina thin, complete, evenly convex mediodorsally.

Mesoscutum and scutellum subpolished, with very fine punctures. Notaulus present on anterolateral side of mesoscutum, weak, with more or less distinct longitudinal wrinkle. Mesopleuron scabrous, impunctate and dull in upper part; with fine punctures on more or less smooth background in lower part. Sternaulus absent. Epicnemial carina extending to about level of lower corner of pronotum, with upper end not reaching anterior margin of mesopleuron. Propodeal spiracle adjacent to pleural carina in holotype and separated from this carina by half diameter of spiracle in paratype. Propodeum scabrous, weakly shining; area basalis small, confluent with areola; areola separated posteriorly from area petiolaris by very weak wrinkle (Fig. 17 ).

Wings as in Fig. 18 . Vein 2rs-m long, much longer than abscissa of M between 2rs-m and 2m-cu. Metacarpus (R1) short, projecting somewhat behind distal end of radial cell. Hind wing with nervellus (cu1&cu-a) intercepted in lower 0.35. Legs moderately slender. Fore tibia with distal outer end pointed (this tooth-like projection shorter than in P. bennetti ). Hind tibia with two short straight spurs.

First metasomal tergite twice as long as posteriorly broad, with large glymma in basal half and spiracle in basal 0.4 (Fig. 19 ). Second tergite distinctly transverse, 0.7 times as long as anteriorly broad. All metasomal tergites dorsally polished and almost glabrous (with a row of fine setae at hind margins), tergite 2 and following tergites with setae laterally. Ovipositor slightly swollen before apex and tapered to a point posterior to swelling (Fig. 20 ); sheath 0.65-0.7 times as long as fore wing, or about 3.5 times as long as hind tibia.

Head predominantly yellow; face and frons medially, vertex and upper part of gena yellowish orange; interocellar area, vertex medially and upper part of occiput blackish (Figs 14 , 15 ). Mouthparts and mandibles (except dark reddish-brown teeth) yellow. Antenna dark brown, scape and pedicel ventrally pale brown. Mesosoma predominantly yellowish orange (Fig. 16 ); metanotum and propodeum dark reddish brown to black; scutellum laterally and metapleuron darkened with reddish brown; mesoscutum with more or less distinct reddish brown or dark brown marks anteriorly, centrally and posteriorly. Tegula yellow. Pterostigma pale brown (Fig. 18 ). Legs rather uniformly yellowish orange to brownish orange, hind coxa somewhat darker (with more intense brownish orange colouration). Tergite 1 dark brown. Metasoma posterior to first tergite dark brown dorsally, brown laterally and yellow ventrally; tergites with pale yellow bands on posterior margins dorsally, pale band very narrow on tergite 2 and broader on following tergites (Fig. 19 ). Ovipositor sheath blackish.

Male. Unknown.

Variation.

The two specimens are almost identical in size, structure and colouration.

Etymology.

The species is named in honour of the collector of the type material, Japanese expert in Ichneumonidae , So Shimizu (Kobe University, Japan).

Material examined.

Holotype female (NIAES), Japan, Honshu I., Kantō Reg., Ibaraki Pref., Kasama City, Hizawa , 36°24'39.3"N, 140°15'6.8"E, ca. 90 m, sweeping on Pinus densiflora , 28.IV.2017, coll. So Shimizu.

Paratype. 1 female (NIAES), same data as holotype .

Distribution.

Japan (Honshu I.).

Figures

Figures 12 - 17. Peucobius shimizui sp. nov., holotype (11, 13 - 15) and paratype (12, 16) females 12 habitus, lateral view 13 antenna 14 head, dorsal view 15 head, front view 16 head and mesosoma, lateral view 17 propodeum, dorsal view.

Figures 18 - 20. Peucobius shimizui sp. nov., holotype female 18 wings 19 metasoma, dorsal view 20 ovipositor, lateral view.

Figures 1 - 3. Peucobius fulvus, female (Canada, Ontario) (1) and P. piceus, female (USA, Colorado) (2, 3). 1, 2 habitus, lateral view 3 propodeum, dorsal view.

Figures 4 - 11. Peucobius bennetti sp. nov., holotype female 4 body, lateral view 5 head, front view 6 clypeus and mandibles, antero-ventral view 7 head and mesoscutum, dorsal view 8 mesosoma and base of metasoma, lateral view 9 fore wing 10 propodeum, dorsal view 11 apex of ovipositor, lateral view.