Microstenus, Szepligeti, 1916

Li, Tao, Sun, Shu-Ping & Sheng, Mao-Ling, 2020, First record of the genus Microstenus Szépligeti (Hymenoptera: Ichneumonidae Cryptinae) from China, with description of one new species and a key to world species, Zootaxa 4838 (4), pp. 594-600 : 595

Key to world species of Microstenus (modified from Gupta & Gupta 1983)

1 Mesopleuron and metapleuron black...................................................................... 2

- Mesopleuron and metapleuron yellowish brown............................................................. 3

2 Pronotum groove and anterior margin of speculum with short ridges; ovipositor sheath about 1.0 × as long as hind tibia; metapleuron rugulose; tergite I (median portion black) yellow.................................... M. falsosus (Tosquinet)

- Pronotum groove smooth; anterior margin of speculum without ridges; ovipositor sheath about 1.1 × as long as hind tibia; metapleuron without rugulose; tergite I (apical portion yellow) black..................... M. mysorensis Gupta & Gupta

3 Malar space about 0.2 × as long as basal width of mandible; tergite I smooth and shiny; metasoma black with yellow bands................................................................................ M. canaliculatus Szépligeti

- Malar space about 0.3 × as long as basal width of mandible; apical portion of tergite I with punctures; metasoma yellowish brown.............................................................................................. 4

4 Epicnemial carina reaching about 0.15 the distance to subtegular ridge; ovipositor sheath about 1.1 × as long as hind tibia; upper margin of pronotum, mesoscutum, base of propodeum dark brown to black; fourth and fifth of hind tarsi brown to dark brown............................................................................ M. philippinus Gupta & Gupta

- Epicnemial carina reaching about 0.3 the distance to subtegular ridge; ovipositor sheath about 0.9 × as long as hind tibia; upper margin of pronotum, mesoscutum, base of propodeum yellowish brown to reddish brown; fourth and anterior half of fifth of hind tarsi yellowish white................................................ M. rufithorax Sheng, Li & Sun , sp. nov.