Taxonomic study of the genus Townesia Ozols (Hymenoptera, Ichneumonidae, Pimplinae) with description of a new species from China and a key to world species

Abstract Five species of the genus Townesia Ozols are reported. One, Townesia sulcata Sheng & Li, sp. nov. collected from Liaoning province, China, is new to science. In addition, digital images and a taxonomic key to the all species of Townesia are presented.


Introduction
Townesia Ozols, 1962, belonging to the tribe Ephialtini of the subfamily Pimplinae (Hymenoptera, Ichneumonidae), comprises four species (Yu et al. 2016), of which two are from the Oriental Region (Gupta and Tikar 1976;Liu and He 2012), two from the Palaearctic Region and one from the Nearctic Region (Sheng and Sun 2010;Townes et al. 1960;Yu et al. 2016). Two species of Townesia were known from China (He et al. 1996;Sheng and Li 2006;Liu and He 2012). The diagnostic characters of the genus were most recently revised by Liu and He (2012) and Townes (1969).
The aim of this article is to describe a new species and provide a key to the world species.

Materials and methods
Specimens were collected with interception traps (IT) (Li et al. 2012) in Chagou, Haicheng, Liaoning Province, P.R. China. The type locality is a forest comprised of mixed deciduous angiosperms and evergreen conifers, mainly including Quercus wutaishanica Mayr, Quercus sp., Larix sp., Castanea spp., and Pinus tabulaeformis Carr.
Type specimens are deposited in the Insect Museum, General Station of Forest and Grassland Pest Management (GSFGPM), National Forestry and Grassland Administration, China.
The specimens of Townesia tenuiventris (Holmgren, 1860), deposited in the Zoologische Staatssammlung München, Germany (ZSM) and identified by Bauer, were examined and compared to the new species. The male characters of T. tenuiventris mentioned in the following key is based on Zwakhals's (2010) description. The photos of holotype of Townesia exilis Gupta & Tikar, 1976, taken by Dr Jonathan Bremer (Florida Department of Agriculture and Consumer Services) was also checked.
Images of the new species were taken using a Stereomicroscope (Leica M205A) with a LAS Montage MultiFocus. Morphological terminology follows Broad et al. (2018).
Diagnosis. Teeth of mandible equal or almost equal. Epomia evidently present. Propodeum elongate, basal portion with median longitudinal impression; pleural carina complete. Areolet subtriangular, receiving 2m-cu slightly distal of middle. Tarsal claws of female with a large basal lobe. Tergite I 0.6-0.7 times as long as tergite II (T. exilis same length), with lateral carina beneath spiracle; basal part of median dorsal carinae distinct. Tergites II to V elongate, with dense punctures. Ovipositor sheath longer than body length, usually about 2.5 times as long as forewing. Apical portion of ventral valve with distinct ridges, subapical portion without or with weak dorsal lobe (Figs 10-14). Description. Female (Fig. 1). Body length approximately 10.4-12.2 mm. Forewing length 7.1-7.8 mm. Ovipositor sheath 11.5-13.1 mm.

Key to world species of Townesia
Head. Face (Fig. 2) approximately 1.2 times as wide as long, smooth with sparse, fine punctures and white hairs; median portion slightly convex. Basal portion of clypeus smooth, with sparse, fine punctures and yellowish-brown hairs; apical portion with dense, fine punctures and short, yellowish-brown hairs; apical margin with deep, median concavity. Malar area with finely granulose texture. Malar space approximately 0.3 times as long as basal width of mandible. Inner orbits of compound eyes convergent downwards. Gena smooth (Fig. 3), with fine, sparse punctures and short, yellowish-brown hairs. Vertex (Fig. 4) smooth, laterally with very sparse punctures, hind part with relatively dense punctures and white hairs. Postocellar line approximately 0.8 times as long as ocular-ocellar line. Upper part of frons with evenly dense punctures and short, white hairs; lower portion concave, with weak, fine, transverse wrinkles. Antenna with 24 flagellomeres, ratio of length from first to fifth flagellomeres: 1.2:1.0:1.0:0.9:0.8. Occipital carina complete.
Coloration (Fig. 1). Black, except following. Maxillary and labial palpi, tegula, and basal portion of fore wing, yellow. Clypeus fusco-testaceous. Legs reddish brown. Fore and mid trochanters yellow; tibia yellowish brown; first to fifth tarsi brown; fifth tarsus dark brown. Hind trochantellus yellow; main portion of tibia yellowish brown to brown, apical portion dark brown; tarsus dark brown to black brown. Veins and pterostigma brown.
Male. Unknown. Etymology. The name of the new species is based on the form of the propodeum which is characterized by having a median, longitudinal groove.

Distribution. China.
Comments. This new species is similar to T. qinghaiensis He, 1996 in having the gena, vertex, mesopleuron (Fig. 6), and propodeum smooth and shiny; propodeum almost without transverse wrinkles; and main portion of hind tibia yellowish brown to brown, with subbasal and apical portion dark brown to black. It can be distin-guished from the latter by the following combination of characters: forewing vein 1cu-a opposite 1/M (distal in T. qinghaiensis), basal 0.6 to 0.7 of propodeum with median longitudinal furrow (absent in T. qinghaiensis), apical portion of ovipositor distinctly curved, dorsal valve smooth, without ridge (Fig. 10), straight and dorsal valve with weak ridges in T. qinghaiensis (Fig. 13), hind coxa red-brown (brownish black in T. qinghaiensis). The new species can be distinguished from all other species by the key provided above. Figure 11 Diagnosis. Forewing length 9.1 mm. Ovipositor sheath length 18.0 mm. Upper tooth of mandible as long as lower tooth. Propodeum with dense punctures and short hairs, without median longitudinal furrow. Tergite I 2.1 times as long as apical width, 0.77 times as long as tergite II. Tergites II-V almost without lateral tubercles. Tergite II as long as tergite III, apical smooth transverse bands 0.15 times as long as respective length. Apical portion of ovipositor evenly curved. Fore coxa yellow. Hind coxa dark brown.

Townesia cheni Liu & He, 2012
Male  Townesia tenuiventris (Holmgren, 1860) Figure 14 Diagnosis. Female: Vertex smooth, shiny, lateral part with sparse, fine punctures. Postocellar line approximately 0.8 times as long as ocular-ocellar line. Upper-posterior part of mesopleuron smooth, shiny, without punctures. Forewing vein radius distinctly basal of middle of pterostigma; 1cu-a distinctly basal of 1/M. Areolet receiving 2m-cu approximately at its posterior 0.3. Tergite II 1.9 times as long as its maximum width, apical smooth transverse bands of tergites II 0.25-2.7 times as long as length. Subapical portion of upper valve of ovipositor with two indistinct tubercles; ventral valve with 10 or 11 ridges, basal 4 ridges strongly inclivous. All coxae, trochanters, and femora reddish brown. Host. Fourteen host species were recorded (Yu et al. 2016). Material examined. The specimens, deposited in ZSM and identified by Bauer, were examined.