Peucobius bennetti Khalaim & Ruiz-Cancino, 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 bennetti Khalaim & Ruiz-Cancino sp. nov.

Figs 4-11

Comparison.

Peucobius bennetti sp. nov. differs from the two other North American species, P. fulvus and P. piceus , by having the frons with a sharp longitudinal carina between the antennal sockets (weakly convex or with rounded longitudinal swelling in P. fulvus and P. piceus ), the occipital carina completely absent in the lower half of the head (complete, or sometimes indistinct near the hypostomal carina in P. fulvus and P. piceus ), deep notaulus (absent or very shallow in P. fulvus and P. piceus ), area basalis of propodeum substituted by a longitudinal keel (Fig. 10 ) (distinct in P. fulvus and P. piceus , see Fig. 3 ), and black and yellow body (Fig. 4 ), while in P. fulvus and P. piceus the body is paler with yellowish markings less contrasting (Figs 1 , 2 ).

Peucobius bennetti sp. nov. also differs from the Eastern Palaearctic P. shimizui sp. nov. by having a shorter metacarpus (R1) of the fore wing, ending just behind the radial cell (Fig. 9 ), while in P. shimizui sp. nov. the metacarpus (R1) extends well beyond the radial cell (Fig. 18 ).

Description.

Female. Body length 4.1 mm. Fore wing length 3.0 mm.

Head with gena strongly rounded posterior to eyes (Fig. 7 ); gena in dorsal view 0.75 times as long as eye width. Clypeus 3.5 times as broad as long (Fig. 6 ), more or less flat medially and with rounded transverse ridge laterally, smooth, with fine punctures in upper half, 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 slightly longer than the upper (Fig. 6 ). Malar space about 0.8 times as long as basal mandibular width, with broad scabrous area between eye and mandibular base. Flagellum with 17 flagellomeres, filiform; three basal flagellomeres 2.5-2.8 times as long as broad; subapical flagellomeres subsquare. Face with conspicuous median swelling, with short and narrow longitudinal furrow on this swelling, with fine and sharp punctures on smooth background laterally, and smooth and almost impunctate centrally on median swelling. Frons with short and sharp longitudinal carina between antennal sockets (just above groove on median swelling); polished and impunctate medially, with fine and sharp punctures laterally. Vertex and gena polished, with very fine setiferous punctures. Occipital carina thin and sharp in upper half of head, evenly convex mediodorsally, and obliterated in lower part (completely absent below level of eye midline).

Mesoscutum polished, centrally almost impunctate, with scattered very fine punctures anteriorly and laterally (Fig. 7 ). Notaulus present on anterolateral side of mesoscutum, short and deep. Scutellum polished, almost impunctate. Mesopleuron subpolished, dull, with very fine inconspicuous punctures in lower part. Sternaulus as weak impression ventrolaterally in anterior part of mesopleuron. Epicnemial carina extending somewhat above level of lower corner of pronotum, with upper end not reaching anterior margin of mesopleuron and slighty curved backwards. Propodeal spiracle separated from pleural carina by almost one times its own maximum diameter. Propodeum almost entirely covered with weak irregular wrinkles, its carinae partly indistinct; area basalis substituted by a single, longitudinal carina; areola about as long as broad, pointed anteriorly, contiguous with area petiolaris posteriorly (Fig. 10 ).

Fore wing as in Fig. 9 . Vein 2rs-m long, somewhat longer than abscissa of M between 2rs-m and 2m-cu. Metacarpus (R1) very short, ending just behind the distal end of radial cell. Hind wing with nervellus (cu1&cu-a) intercepted in lower 0.45. Legs moderately slender. Fore tibia with long tooth on distal outer side. Hind tibia with two short spurs which are slightly curved at apex.

First metasomal tergite 1.8 times as long as posteriorly broad, with large glymma in basal half (Fig. 8 ); dorsally tergite 1 polished, finely striate in basal half. Second tergite distinctly transverse, 0.65 times as long as anteriorly broad. Tergites 2 to 6 dorsally highly polished and almost glabrous (with row of fine setae at hind margins), laterally tergites 2 and 3 with rather dense setae and following tergites laterally with sparse setae. Ovipositor slightly swollen before apex and tapered to a point posterior to swelling (Fig. 11 ); sheath as long as fore wing, or 3.0 times as long as hind tibia.

Head predominantly black; clypeus, face, frontal orbits (extending above to level of hind end of lateral ocelli) and lower third of gena yellow (Figs 4 , 5 , 7 ); median third of gena brownish. Mouthparts and mandible (except brownish black teeth) yellow. Antenna black, scape and pedicel ventrally brownish yellow. Mesosoma black; propleuron and front margin of pronotum dark brown (Fig. 8 ). Tegula yellow. Pterostigma brown with yellowish spot at base (Fig. 9 ). Fore leg with coxa and trochanters yellow (coxa slightly darkened at extreme base); femur, tibia and tarsus brownish yellow (femur apically yellowish). Mid leg predominantly brownish yellow with coxa extensively darkened with brown and tarsus infuscate. Hind leg with coxa almost entirely brownish black (except pale brown extreme apex), trochanters and femur brownish yellow with extensive dark brown markings on dorsal side, and tibia and tarsus more or less entirely brownish yellow. Tergite 1 black. Metasoma posterior to first tergite dorsally and laterally dark brown (anteriorly) to brown and yellow (posteriorly), ventrally and on hind margins of tergites yellow (Fig. 4 ). Ovipositor sheath dark brown basally to black apically.

Male. Unknown.

Etymology.

The species is named in honour of the Canadian expert in Ichneumonidae , Andrew M.R. Bennett (CNC).

Material examined.

Holotype female (UNAM), Mexico, Tlaxcala, Nanacamilpa, Ejido Los Bufalos , 19°28'N, 98°35'W, bosque pino-encino ( Pinus + Quercus forest), 2830-2900 m, Malaise trap, 4.IV-3.V.2016, coll. Y. Marquez & A. Contreras.

Distribution.

Mexico (Tlaxcala).

Figures

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.

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