Chinese species of genus Notopygus Holmgren (Hymenoptera, Ichneumonidae, Ctenopelmatinae) with description of a new species

Abstract A new species, Notopygus longiventris Sun & Sheng, sp. n., collected from Benxi County, Liaoning Province, China, and N. emarginatus Holmgren, 1857, reared from Neurotoma sibirica Gussakovskij (Hymenoptera, Pamphiliidae) from Haicheng, Liaoning Province, are reported. The new species is placed within existing key to species.


Introduction
Notopygus Holmgren, 1857, belonging to the tribe Ctenopelmatini of the subfamily Ctenopelmatinae (Hymenoptera: Ichneumonidae), comprises 16 species (Yu et al. 2012), of which one is from the Oriental Region, nine from the Western Palaearctic (five of them also found in the Eastern Palaearctic), six from the Eastern Palaearctic and four are from the Nearctic. The Palaearctic species were revised by Kasparyan (2002). A key to the species of the Eastern Palaearctic Region was given by Kasparyan and Khalaim (2007). The status of the genus was elucidated by Townes (1970) and by Kasparyan (2002).
Two species have been known from China, of which one, N. emarginatus Holmgren, 1857, found in Liaoning, was previously mistaken for N. insignis Kriechbaumer, 1891(Chen et al. 2007. Notopygus raricolor (Aubert 1985), found in Sichuan, was originally described only from the male, and was redescribed, and its systematic position discussed by Kasparyan (2002).
In this article, three species of Notopygus are reported, of which one was reared from Neurotoma sibirica Gussakovskij (Hymenoptera, Pamphiliidae) in Haicheng, Liaoning Province, and one collected from Benxi, Liaoning Province, is new to science.

Materials and methods
The unique specimen of Notopygus longiventris Sun & Sheng, sp.n. was collected by intercept trap (Li et al. 2012) in the forests of Benxi County, Liaoning Province (China). Specimens of N. emarginatus were reared from Neurotoma sibirica Gussakovskij (Hymenoptera, Pamphiliidae) in Haicheng, Liaoning province, and collected while they were ovipositing into their hosts (Figure 11), as well as being collected with intercept traps and hand nets in the forests of Benxi and Kuandian, Liaoning province. The forest of Benxi is composed of mixed deciduous angiosperms and evergreen conifers, mainly comprising Pinus koraiensis Sieb. & Zucc., Acer mono Maxim., Juglans mandshurica Maxim., Prunus padus L., Fraxinus rhynchophylla Hance and Ulmus pumila L. The forest of Kuandian is composed of mixed deciduous angiosperms, mainly comprising Quercus wutaishanica Blume, Celtis bungeana Bl., Larix gmelinii (Rupr.) Rupr., Prunus padus and Fraxinus rhynchophylla.
Images of whole insects were taken with a Canon Power Shot A650 IS. Other images were taken using a Cool Snap 3CCD attached to a Zeiss Discovery V8 Stereomicroscope and captured with QCapture Pro version 5.1.
Specimens were compared with material from the Natural History Museum (NHM), London, UK and the Zoologische Staatssammlung München (ZSM), Germany.
The type specimen is deposited in the Insect Museum, General Station of Forest Pest Management (GSFPM), State Forestry Administration, People's Republic of China.  Head. Face (Fig. 2) 1.7 times as wide as long, median portion slightly convex longitudinally; with uneven punctures and longitudinal wrinkles; upper margin with a small median tubercle; between antenna socket and eye with obvious longitudinal concavity. Clypeus 3.3 times as wide as long, with shallow uneven punctures, median section of apical margin thick. Mandible (Fig. 2) distinctly elongate, with dense longitudinal wrinkles and fine punctures; upper tooth slightly shorter than lower tooth. Subocular sulcus absent. Malar space 0.17 times as long as basal width of mandible. Gena in dorsal view slightly longer than length of eye, with dense fine punctures and a few large uneven punctures. Vertex (Fig. 3) with dense indistinct punctures, postero-median portion distinctly concave. Postocellar line as long as ocular-ocellar line. Dorsal half of frons flat, with indistinct, weak, irregular wrinkles; lower half deeply concave, smooth, shiny. Antenna with 40 flagellomeres; ratios of lengths from first to fifth flagellomeres: 2.3:2.2:2.0:1.8:1.7. Occipital carina complete, lower end joining hypostomal carina at base of mandible.
Metasoma. First tergite about 1.9 times as long as apical width; median dorsal carinae reaching apical 0.2; interspace between median dorsal carinae slightly concave and almost smooth and shiny. Lateral parts of postpetiole with dense transverse wrinkles. Dorsolateral and ventrolateral carinae complete. Spiracle circular, small, evidently convex, located at middle of first tergite. Second tergite (Fig. 9) almost shiny, 1.27 times as long as basal width, 0.93 times as long as apical width; basal 0.35 with a pair of median longitudinal carinae; from spiracle to base with a strong carina; with shallow, sparse, uneven punctures. Third and following tergites slightly shagreened. Third tergite with shallow, small, indistinct punctures; 0.95 times as long as basal width, 1.03 times as long as apical width. Lateral margins of tergites 4 to 6 almost parallel. Tergite 7 transverse. Tergite 8 smooth, shiny, basal-median portion concave, apical portion weakly projecting upwardly. Sternites 4 to 6 strongly sclerotized.
Color (Fig. 1). Black, except the following. Flagellomeres 18 to 27 white. Lateral portions of clypeus, maxillary and labial palpi yellowish brown. Median portion of mandible reddish brown, basal blackish brown, teeth black. Upper-posterior corner of pronotum, tegula, small indistinct spot on subalar ridge, anterior and middle legs except coxae, apical apex of hind trochanter, extreme base of hind femur, hind tibia except apical portion brownish black and base slightly blackish, reddish brown. Apical portion of tergite 1, tergites 2 and 3, basal portion of tergite 4, lateral portions of tergites 5 and 6 brownish red. Pterostigma blackish brown. Veins brownish black.
Remarks. This new species is similar to N. emarginatus Holmgren, 1857, andN. eurus Kasparyan, 2002, in having a white ring on the antenna, tergite 2 with a pair of median longitudinal carinae in basal portion, mandible partly brownish red, median tergites usually reddish brown, but can be distinguished from N. emarginatus by the key mentioned above, and can be distinguished from N. eurus by the following combination of characters. Frons strongly divided into two parts, lower part deeply concave, smooth; dorsal part flat, with indistinct, weak, irregular wrinkles. Scutoscutellar groove with short longitudinal wrinkles. Fore wing with vein 1cu-a distal to 1/M. Hind wing vein 1-cu 2.0 times as long as cu-a. N. eurus: Frons not separated into two parts. Scuto-scutellar groove smooth without longitudinal wrinkles. Fore wing with vein 1cu-a opposite 1/M. Hind wing vein 1-cu about as long as or slightly longer than cu-a.