Coelichneumon rufibasalis ( Uchida, 1927 )

Riedel, Matthias & Watanabe, Kyohei, 2021, The genus Coelichneumon Thomson in Japan (Hymenoptera, Ichneumonidae, Ichneumoninae), Zootaxa 4948 (4), pp. 501-545 : 534-535

Coelichneumon rufibasalis ( Uchida, 1927)

Ichneumon rufibasalis Uchida, 1927: 196 , ♂.

Holotype: ♂ “Maruyama 4/7.1926, Hokkaido Uchida; [red] Type Matsumura; Ichneumon . rufibasalis sp.n. ” ( Sapporo ), type studied.

Non-type material: JAPAN: 1♂. Hokkaido, Tomakomai City, Exp. Forest of Hokkaido University , 18– 20.vi.1980, K. Maeto leg. ( NIAES) ; CHINA: 1 ♀ & 1 ♂, Beijing municipaly, Xiaolongmen Nat. Park , 39.58°N 115.26°E, 4–10.vi.2016, E. Jendek & O.Sausa leg. (Biozentrum Linz) ; MONGOLIA, 1 ♀, 100 km E Ulanbatar, 20 km NE Tereltz, Tuul river , 15–21.vii.2003, J. Halada leg. ( Biozentrum Linz ) .

Description (based on Chinese material): ♀: Body length 18 mm. Flagellum with 51‒52 flagellomeres, strongly lanceolate; 1 st flagellomere 1.9‒2.0× and 2 nd flagellomere 1.9× longer than wide, combined length 0.56× eye length, 9 th flagellomere square; widest flagellomeres 2.5‒2.7× wider than long. Temple long, slightly and roundly narrowed behind eye. OED 1.3× ocellar diameter. Frons finely and transversally rugose-punctate. Face densely punctate. Clypeus partly with scattered punctures, apical margin slightly bulging medially. Gena laterally 1.2× wider than eye, with scattered punctures ventrally. MI 0.6.

Mesosoma with fine pale brownish hairs. Notaulus distinct in anterior 0.3 of mesoscutum. Mesoscutum densely punctate, granulate, slightly shining. Mesopleuron and metapleuron with coarse dense punctures, shining. Juxtacoxal carina present. Scutellum moderately elevated, slightly longer than wide, with rather dense punctures, without lateral carina. Area superomedia heart-shaped, slightly longer than wide, finely granulate. Hind coxa densely punctate, with strong scopa (0.25× as long as coxa). Hind femur 3.7‒3.9× longer than wide, with dense punctures. 3 rd mid tarsomere rather slender, 1.5‒1.7× longer than wide.

Areolet pentagonal, frontal distance between veins 2rs-m and 3rs-m 2× their width; vein 2m-cu in its middle. Vein 1cu-a postfurcal by 2× its width.

Postpetiolus strongly widened; lateral field 0.4× as wide as median field, rugose-punctate; median field slightly elevated, with fine longitudinal rugae and coarse punctures. Gastrocoelus strongly impressed, with strong ridges. Thyridium almost transverse, 0.8× as wide as the interval. 2 nd tergite 0.9× as long as wide. 2 nd and 3 rd tergites finely and densely rugose-punctate, granulate; 2 nd tergite medially with fine striae in the anterior half. Ovipositor sheath not extending behind metasomal apex.

Color: black. Stripes of flagellomeres 7/9‒14, narrow frontal orbit, sickle-shaped spot on vertex, sometimes spot on collare and hind edge of pronotum, entire or apical ¾ of scutellum, sometimes postscutellum and usually small frontal spots in fore and mid coxae yellow. 2 nd and 3 rd tergites and sternites red, sometimes also hind margin of postpetiolus and basal half of 4 th tergite. Legs blackish; fore and mid legs ± ochreous frontally; hind femur sometimes narrowly reddish basally; hind tibia diffusely reddish in basal ½‒3/4, sometimes with small yellow spot basally. Wings slightly infuscate, pterostigma brown or black.

♂: Body length 17.5 mm. Antenna with 42 flagellomeres; 1 st flagellomere 1.7‒1.8× longer than wide. Tyloids on flagellomeres 7‒16, oval, small, c. 0.3× as long as their flagellomeres, situated in their center. Temple distinctly and almost linearly narrowed behind eye, dorsally 0.8× as long as eye. OED 1.3× ocellar diameter. Frons punctate. Face and clypeus densely punctate and finely granulate. Gena laterally 1.0× as wide as eye, densely punctate. MI 0.3.

Mesosoma covered with grey hairs. Notaulus impressed in frontal margin of mesoscutum. Mesoscutum densely punctate, partly rugose-punctate, shining. Mesopleuron and metapleuron densely punctate; juxtacoxal carina present. Scutellum moderately elevated, about as long as wide, finely punctate, with lateral carina in basal 0.2‒0.4. Area superomedia halfmoon-shaped, slightly wider than long, smooth or finely coriaceous centrally, apical carina absent; anterior transversal carina absent or weakly indicated. Area petiolaris transversely rugose-punctate, with lateral carina. Fore metatarsus with strong apical tooth. Hind femur 3.6‒3.7× longer than wide. Areolet pentagonal, frontal distance between veins 2rs-m and 3rs-m 1× their width; vein 2m-cu slightly distad its middle. Vein 1cu-a postfurcal by 2× its width.

Postpetiolus moderately widened; lateral field 0.40‒0.45× as wide as the median one, punctate; median field slightly elevated, with fine aciculation. 2 nd tergite 1.0‒1.05× as wide as long. Gastrocoelus strongly impressed, with distinct oblique ridges. Thyridium oblique, c.1.2× wider than the interval. 2 nd tergite densely punctate and with longitudinal rugae medially, with strong striae between thyridia. 3 rd and 4 th tergites with fine dense punctures and ± granulate.

Color: Black. Palps, mandible except teeth, side of clypeus, wide facial orbit, facial spot below antennal socket, small vertical spot, hind edge of pronotum, spot on tegula, subtegular ridge, apical 2/3 of scutellum, and frontal spots on fore and somtimes mid coxae yellow. Metasoma black; sometimes posterolateral spot on postpetiolus, 2 nd tergite entirelz and 3 rd and 4 th tergites laterally reddish (in holotype) or chestnut-brown (in Far East Russian specimen). In holotype, legs except coxae and trochanters reddish; fore and mid femora basally and hind femur except red base black; hind tibia black in apical 0.4. Legs in Far East Russian specimen black; fore and mid femora apically, bases and frontal stripes of all tibiae and all tarsomeres except their tips ivory (4 th and 5 th hind tarsomeres blackish). Wings hyaline; pterostigma dark reddish-brown or brown.

Remarks: This is the first record of female and of this species from China and Mongolia.

Distribution: Japan (Hokkaido), China, Mongolia, Korea and Far East Russia ( Riedel 2020).