The genus Rhynchobanchus Kriechbaumer in China, with descriptions of a new species and first record of the genus from Oriental region (Hymenoptera, Ichneumonidae, Banchinae)

Abstract Six species and two subspecies of the genus Rhynchobanchus Kriechbaumer, 1894 are reported from China, of which one, Rh. flavomaculatus Sheng, sp. n., is a new species and the first record of the genus from the Oriental Region. Rhynchobanchus flavopictus orientalis Kuslitzky, 2007 is a new Chinese record. A key to the species of Rhynchobanchus occurring in China is provided.


Introduction
Rhynchobanchus Kriechbaumer, 1894, belonging to the tribe Banchini of the subfamily Banchinae (Hymenoptera: Ichneumonidae) and comprising seven species (Yu et al. 2016), is only known from the Palaearctic Region (Kriechbaumer 1894;Meyer 1927;Sheng et al. 1995Sheng et al. , 1997Kuslitzky 2007;Kim et al. 2012;Sun 2014, Watanabe 2016). Four species restricted to the Eastern Palaearctic Region, one to the West-ern Palaearctic Region, and two species are trans-Palaearctic. The diagnostic characters of the genus were most recently revised by Sheng et al. (2014).
The aim of this study is to revise all available materials of Rhynchobanchus from China, describe one new species from the Oriental part of China, and provide an identification key to species occurring in China.

Materials and methods
Type specimens were collected using entomological sweep nets in the forest of Tianmu Mt., Lin'an, Zhejiang Province and Shaoyang, Hunan Province (China). Other Chinese specimens from the collections in the Insect Museum, General Station of Forest Pest Management, State Forestry Administration, People's Republic of China (GSFPM) were checked.
All examined material, including type specimens of the new species, is deposited in GSFPM.
Host. Unknown. Diagnosis. Body yellowish brown with large irregular yellowish white spots (Fig. 1). Face (Fig. 2) finely granulose, with sparse fine punctures and yellowish brown setae, near upper margin with a small median tubercle. Inner orbits of compound eyes distinctly emarginate opposite antennal sockets, with regular yellowish brown setae. Posteromedian portion of vertex (behind ocellar triangle) with weak longitudinal groove (Fig. 3). Lower-posterior corner of mesopleuron with strong swelling (Fig. 5). Wings (Fig. 7) yellowish brown, semi-hyaline. Longer spur of mid tibia approximately 0.8 times as long as first tarsomere. Tergite 1 about 2.3 times as long as apical width, distinctly convex basal of spiracle.

Key to females of species of Rhynchobanchus known in China
Description. Female (Fig. 1). Body length 15.6 to 17.1 mm. Forewing length 11.3 to 12.9 mm.
Legs. Dorsal profile and apical portion of tibia with uneven thorns. Longer spur of mid tibia 0.8 times as long as first tarsomere. Ratio of length of hind first to fifth tarsomeres 5.8:2.5:2.0:1.0:1.5.
Metasoma. Tergite 1 about 2.3 times as long as apical width, distinctly convex basal of spiracle, with fine punctures and yellowish brown short setae, apical margin smooth; glymma deep, small; spiracle small, convex, almost circular, located at basal 0.3. Tergite 2 (Fig. 8) approximately as long as apical width, indistinctly reticular, with dense punctures and yellowish brown short setae; basal median portion transversely convex, smooth; thyridium distinct, almost smooth. Tergite 3 weakly shining, with dense fine punctures and yellowish brown setae, apical portion slightly compressed. Fourth and subsequent tergites compressed, with fine punctures and yellowish brown setae. Ovipositor sheath broad, not reaching to apex of metasoma.
Colour pattern (Fig. 1). Yellowish brown with large irregular yellowish white spots, except following: mandibular teeth, median portion of frons, ocellar triangle, line along occipital carina, anteromedian narrow reversed triangular spot, scutoscutellar groove, anterior portion of mesosternum, anterior margin of metapleuron, anterior transverse groove of propodeum, front and inner profiles of hind coxa, trochanter (dorsal and apical portions reddish brown), median portion of tergite 1 irregularly dark brown to black. Antenna except apical portion brown to dark brown, main portion of front femur, ventral profile of mid femur slightly; apical margin of hind coxa, hind trochantellus, hind femur, hind tibia except basal half yellowish brown, hind tarsus; tergites 2 and 3 except apical triangular spots yellow to brown, tergites 3 to 7 except lateral and apical margin yellow to yellowish brown; tergite 8, ovipositor sheath reddish brown to dark reddish brown. Pterostigma brown. Veins brown to dark brown.
Male. Body length approximately 13.1 mm. Forewing length approximately 10.0 mm. Antenna with 55 flagellomeres. Lateral longitudinal stripes of mesoscutum, transverse stripe beneath subalar ridge black brown to brown. Pterostigma yellowish brown. Otherwise similar to female.
Remarks. This new species is similar to Rh. maculicornis Sheng et al., 1995, but can be distinguished from the latter by the following combination of characters: lowerposterior corner of mesopleuron with strong convexity; gena, vertex, mesopleuron and mesosternum yellow; and propodeum yellowish white. Rhynchobanchus maculicornis has lower-posterior corner of mesopleuron slightly convex; gena, vertex, mesopleuron and mesosternum black; basal portion of propodeum black, median reddish brown and apical yellow.
Etymology. The name of the new species is derived from Latin words "flavi" (yellow) and "maculatus" (macula) after its body with large irregular yellowish spots.        (Uchida, 1933). Female. Tergites I-II, dorsal view. Figure 14 Specimens examined.

Conclusions
There are now eight known species of Rhynchobanchus Kriechbaumer in the world, of which one is only known from the Oriental Region, and seven species are known from the Palaearctic Region. Six species have been known from China. Hitherto, there are no host records.