The genus Gyrodonta Cameron , with description of a new species and a key to species ( Hymenoptera , Ichneumonidae , Ichneumoninae )

A new species, Gyrodonta motuoica sp. n., collected from Motuo County, Xizang Autonomous Region, China is described. Gyrodonta concava (Uchida, 1937), previously known from Jiangxi, is reported from Hunan Province, China, and Nepal for the first time. Illustrations of both species are provided, as well as a key to species.


Introduction
Gyrodonta Cameron, 1901, belonging to the tribe Ichneumonini of the subfamily Ichneumoninae (Hymenoptera: Ichneumonidae) and distributed in the Oriental Region, comprises two species (Yu et al. 2012), one of which, G. concava (Uchida, 1937), is from Jiangxi Province, China, and one, G. flavomaculata Cameron, 1901 is from India.
Gyrodonta was originally placed in its own tribe because it is so unusual-looking, distinctive within Ichneumoninae (Cameron, 1901).But Narayanan and Lal (1958) included it in the tribe Ichneumonini.Townes et al. (1961) transferred Pielia concava Uchida, 1937 to Gyrodonta and kept it in their tribe Joppini (Ichneumonini of other authors) in their reclassification of Indo-Australian Ichneumonidae.Gupta (1987) followed Schmiedeknecht's (1902) opinion, as a valid tribe Gyrodontini.Wahl and Mason (1995) used out Gyrodontina Schmiedeknecht, 1902 as a valid subtribe within the Ichneumonini.In the "world catalogue" (Yu and Horstmann 1997) and database (Yu, Achterberg and Horstmann 2012), Gyrodonta Cameron was again included in the Ichneumonini, as they do not list subtribes.We agree with Wahl & Mason's standpoint, Gyrodonta Cameron, 1901 belongs to the subtribe Gyrodontina within the tribe Ichneumonini.
In this article, one new Gyrodonta species, collected in Xizang Autonomous Region, China, and another species, collected in Hunan and in Nepal, previously known from Jiangxi, are described.

Material and methods
The holotype of Gyrodonta motuoica sp.n. was collected by Tao Li in Motuo County, Xizang Autonomous Region (China) on a blacklit sheet at night.The specimens of G. concava (Uchida, 1937) were collected by Ze-Jian Li (Lab of Insect Systematics and Evolutionary Biology, Central South University of Forestry and Technology, Changsha, China) using entomological nets in the forest of Mufushan, Hunan Province (CHINA) and by P. Cechovsky using a Malaise trap in Nepal.
Images were taken using a Leica M205A Stereomicroscope with LAS Montage MultiFocus.
All specimens, except one of G. concava from Nepal in the Biozentrum Linz, Austria, are deposited in the Insect Museum, General Station of Forest Pest Management (GSFPM), State Forestry Administration, People's Republic of China.
Head.Face (Figure 2) slightly concave, with sparse, weak punctures; median portion with indistinct longitudinal wrinkles; upper margin with weak median triangular convexity; from outside of antennal socket to inner side of clypeal foveae with distinct oblique groove.Clypeus with different texture from face, shiny, irregularly longitudinally convex medially; subapical portion with sparse, indistinct, fine punctures; median section of apical margin almost truncate.Mandible large, basal half longitudinally concave medially, with sparse, fine punctures; upper marginal tooth (Figure 3) located at center.Malar area finely alutaceous; malar space approximately 0.9 times as long as basal width of mandible.Gena (Figures 4, 7) almost shiny, with distinct punctures, lower portion with indistinct wrinkles.Vertex with distinct, fine punctures.Interocellar  area with distinct longitudinal groove.Postocellar line approximately 0.5 times as long as ocular-ocellar line, 0.87 times maximum diameter of posterior ocellus.Frons (Figure 5) deeply concave, with distinct transverse wrinkles; lower portion with distinct median longitudinal carina.Antenna (Figure 6) slightly longer than head and mesosoma combined, with 38 flagellomeres; apical portion of flagellum distinctly flattened below; ratio of length from first to fifth flagellomeres: 7.0:6.0:5.5:5.2:5.0.Occipital carina complete, lower end joining hypostomal carina slightly above base of mandible.
Metasoma.First tergite approximately 3 times as long as apical width, dorsal profile of petiole with sparse punctures, lateral with indistinct longitudinal wrinkles (Figure 12).Postpetiole (Figure 13) with dense punctures, distance between punctures 0.5-2.5 times their diameter; lateral and apical portions shiny, very sparsely punctate.Second tergite (Figure 13) approximately 1.25 times as long as apical width, with fine punctures, distance between punctures 1.0-3.0times their diameter.Third tergite approximately 0.9 times as long as apical width, with fine indistinct punctures.Ovipositor sheath reaching to apex of metasoma.
Color (Figure 1).Head mainly brownish black; face and clypeus reddish brown; inner orbits irregularly, malar area, lower portion of gena, flagellomeres (apical portion of 9)10-16 white; median longitudinal portion of mandible, scape, apical ventral profile of flagellum dark brown.Mesosoma black.Dorsal anterior margin, upper margin and lower anterior corner of pronotum, longitudinal band of tegula, scutellum almost entirely, subtegular ridge, large median spot of mesopleuron, posterior lateral portion of propodeum white.Sublateral longitudinal band of mesoscutum dark brown.Femora, tibiae, main portion of anterior and mid coxae, anterior-basal spot of hind coxa, lower profiles of anterior and mid trochanters brownish red.Main portions of anterior and mid coxae, dorsal profiles of trochanters, apical margin and dorsal spot of hind coxa white.Tarsus buff.Tergites brown red.Basal portion of first tergite, hind margins of fourth and subsequent tergites more or less darkish brown.Pterostigma brown.Veins brownish black.
Remarks.This new species is similar to G. concava (Uchida, 1937) but can easily be distinguished from the latter by the following combination of characters: apical portion of flagellum distinctly flattened below; upper marginal tooth of mandible located at middle; propodeum without costula, median longitudinal carinae vestigial; second tergite (Figure 13) 1.25 times as long as apical width, with distinct, fine punctures.Gyrodonta concava: apical portion of flagellum cylindrical; upper marginal tooth of mandible located subbasally; propodeum with distinct costula and median longitudinal carinae; second tergite almost 1.1 times as long as apical width, finely coriaceous, without punctures.

Specimens not examined.
Distribution.India.