(Hymenoptera: Ichneumonidae: Banchinae) GR

Труды Русского энтомологического общества. С.-Петербург, 2014. Т. 85(1): 63–76. Proceedings of the Russian Entomological Society. St Petersburg, 2014. Vol. 85(1): 63–76. A revision of Sachtlebenia Townes, with notes on the species of Townesion Kasparyan (Hymenoptera: Ichneumonidae: Banchinae) G.R. Broad Ревизия рода Sachtlebenia Townes с замечаниями к видам Townesion Kasparyan (Hymenoptera: Ichneumonidae: Banchinae) Г.Р. Броад Department of Life Sciences, The Natural History Museum, Cromwell Road, London SW7 5BD. E-mail: [email protected] Abstract. The genus Sachtlebenia (Ichneumonidae: Banchinae) is revised and two new species described, S. dmitrii sp. n. from Vietnam and S. gillae sp. n. from Brunei. The two species of the related genus Townesion are distinguished and T. japonicus Kasparyan is newly recorded from Russia (Sakhalin). Synapomorphies are proposed for Sachtlebenia and Townesion. Key words. Taxonomy, parasitoid. Резюме. Ревизован род Sachtlebenia (Ichneumonidae: Banchinae), в котором описаны 2 новых вида: S. dmitrii sp. n. из Вьетнама и S. gillae sp. n. из Брунея. В родственном роде Townesion рассмотрены 2 вида, включая T. japonicus Kasparyan, который впервые отмечен с Сахалина (Россия). Предложе- ны синапоморфии для родов Sachtlebenia и Townesion. Ключевые слова. Систематика, паразитоид. Introduction The genera Sachtlebenia Townes and Townesion Kasparyan (Hymenoptera: Ichneumonidae) com- prise a strikingly aberrant and distinctive pair of genera. Unlike any other ichneumonids, the second to fourth metasomal tergites are much more strongly sclerotized than the posterior tergites, which are hidden under the fourth tergite, and the metasomal insertion is high above the hind coxal insertions. Two genera of Cryptinae, Hemigaster and Rothneyia, have a similar sclerotization of the metasoma but differ most obviously in the petiolate first metasomal segment that is inserted level with the hind coxae. Restricted to Eastern Asia, both Sachtlebenia and Townesion are very rare in collections but recent collecting in the Eastern Palaearctic and Oriental regions has produced two undescribed species of Sachtlebenia and addi- tional specimens of Townesion, which are described here. Gauld and Wahl (2000) established that these aberrant genera should not be treated as a separate subfamily, Townesioninae, as had been proposed by Kasparyan (1993) but instead comprised a highly apomorphic lineage of the tribe Glyptini, of the subfamily Banchinae. Although Gauld and Wahl (2000) proposed several apomorphic characters that support the placement of the so-called townesionine genera in the Glyptini, it should be noted that the single molecular phylogenetic study including a representative of this clade (Townesion ussuriensis Kasparyan) failed to recover this taxon within the Banchinae (Quicke et al., 2009), although only a single gene was se- 63 quenced. Pending a more robust molecular phylogenetic analysis, Gauld and Wahl’s (2000) conclusions are followed here. Although Gauld and Wahl (2000) did not question the monophyly of each genus, in light of their striking similarities, I have tried to identify apomorphies that define each as reciprocally monophyletic genera. Material and methods Morphological terminology follows Gauld (1991). Photographs were taken using a Canon EOS 450D digital camera attached to a Leica MZ12 stereomicroscope. Partially focused photographs were combined using Helicon Focus software. Specimens from the following institutions were examined: American Entomological Institute, Gainesville, Florida, USA (AEI); The Natural History Museum, Lon- don, UK (BMNH); Ehime University, Japan (EUMJ); General Station of Forest Pest Management, State Forestry Administration, Shenyang, China (GSFPM); Naturalis Biodiversity Centre, Leiden, Netherlands (RMNH); Texas A&M University Insect Collection, College Station, Texas, USA (TAMU). Taxonomic part Sachtlebenia and Townesion are clearly closely related and are unlikely to be confused with any other genera of Ichneumonidae. Gauld and Wahl (2000) suggested nine apomorphies for this clade, the most distinctive of which are the high insertion of the metasoma to the propodeum; metasomal segments five to nine retracted beneath the fourth tergite (Figs 2, 7); mesoscutum with a posterior transverse suture (Fig. 3); the deeply impressed, narrow malar groove (Fig. 1); and fore wing vein Rs+2r arising from the proximal 0.3 of the elongate pterostigma (Fig. 2b). Characters that are shared with the genus Sjostedtiella Szépligeti include the flat clypeus; tapered, slightly twisted mandibles; goblet-shaped antennal scape (Fig. 1); and the epomia strong, long, paralleling the anterior margin of the pronotum. Additionally, the triangular areas on the second to fourth tergites, delimited by paired, lateromedian grooves, distinguish the tribe Glyptini (other ichneumonids with diagonal grooves on the metasoma, such as some Pimplinae and Lycorina Holmgren, differ in the precise pattern of grooves). In the generic treatments that follow, full descriptions and brief diagnoses of the two genera are included. Species descriptions and diagnoses concentrate on characters of value at the species level and do not repeat most of the generic characters listed here or by Gauld and Wahl (2000). Because of the close similarity of all species within each genus, the descriptions concentrate on colour patterns and the shape of the posterior apex of the fourth tergite. The two “townesionine” genera can be distinguished from each other as follows. 1. Ground colour pale yellow or ivory, with restricted dark markings; malar space about 2.0 times basal mandibular width; face conspicuously raised relative to malar groove and with central area separated by faint grooves (Fig. 1a); fourth metasomal tergite with a pair of lateral projections...... Sachtlebenia – Ground colour black with restricted pale markings; malar space slightly shorter than basal mandibular width; face not raised, uniformly convex (Fig. 1b); fourth metasomal tergite with two pairs of lateral and lateromedian projections ............................................................................................ Townesion Sachtlebenia Townes, 1963 Described for the distinctive Sachtlebenia sexmaculata Townes, no other species of Sachtlebenia have been described until now and specimens are present in very few collections. Species are restricted to the Oriental region, although S. sexmaculata has been collected towards the northern edge of Oriental China, in Jiangxi Province (Sheng et al., 2013). This is clearly a very infrequently collected genus. The new species from Brunei and Vietnam are each known only from only one and two specimens respec- tively, each from quite large-scale collecting effort that resulted in collections of thousands of ichneumonids. Clearly there is potential for further finds. Description. Fore wing 5.9–7.5 mm. Malar space long, about 2.0 times basal mandibular width, with sharply defined, narrow sulcus; clypeus not distinctly separated from face, rather flat; mandibles slender, slightly twisted; face swollen, noticeably bulging on inner side of malar groove then slightly concave, convex centrally with vague grooves either side of convexity, with fine striae on lateral convexities and clypeus, coarsely punctate/puncto-striate over remainder of face; 64 antenna long, with 50–53 flagellomeres, scape short, goblet-shaped; frons without a medial projection; occiput not strongly impressed, lacking vertical ridges. Mesosoma not especially bulging, posterior edge of pronotum slightly curved; mesopleuron dorsally punctate, otherwi- se unsculptured, smooth; epicnemial carina present; upper division of metapleuron distinct, raised; epomia strong, paralleling anterior margin of pronotum; mesoscutum with transverse suture posteriorly and scutoscutellar groove trans- striate. Propodeum with posterior transverse carina fairly well-defined, ranging from complete to only present laterally; propodeal spiracle elongate. Fore tibial spur 0.25 times length of first tarsomere; fore and mid-tarsal claws fully pecti- nate, hind claw only with basal one or two teeth. Metasomal foramen dorsal to, widely separated from hind coxal foramina; first metasomal tergite without anterolateral angulate projections (teeth), lacking defined medial and lateral cari- nae; metasoma with deep grooves on tergites two-four, delimiting anteriorly pointing trian- gles, although grooves weaker on tergite four; tergites not strongly convex in lateral view; fourth tergite posteriorly with paired lateral projections of varying development, with thin, tran- slucent flange or lamella developed to varying extent between projections; fifth to ninth tergites retracted beneath fourth tergite. Ovipositor very short, abruptly narrowed near base, needle- like over most of its length. Ground colour pale yellow or creamy white with restricted black markings on metasoma, legs and sometimes on dorsum of mesosoma and head. Fore wing with triangular, petiolate areolet, vein 2m-cu opposite 3rs-m; pterostigma long, narrow, with Rs+2r arising from proximal 0.3; fore wing with infus- cate band along distal edge, well-defined or only vaguely defined. Comparative diagnosis. Sachtle- Figure 1. Head, frontal view: a – Sachtlebenia sexmaculata, b – benia can be distinguished from all other Townesion ussuriensis. ichneumonids by the combination of the metasoma arising from the propodeum far above the hind coxae; the fifth and following metasomal tergites retracted beneath

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