Key to the known species of Bathanthidium

(Females of B. bicolor, B. monganshanense, males of B. fengkaiense, B. hainanense, B. emeiense unknown, not be included in the key)

1 Flagellum 10-segmented, female......................................................................... 2

- Flagellum 11-segmented, male.......................................................................... 11

2 Fovea behind propodeal spiracle rounded, delimited by strong carina....................... 3 B. ( Bathanthidium s. str.)

- Fovea behind propodeal spiracle elongate, weakly delimited................................................... 5

3 Paraocular area with thin and long yellow marking extending along the inner margin to the top of the eye......................................................................... B. ( Bathanthidium s. str.) bifoveolatum (Alfken, 1937)

- Paraocular area near ventral extreme with a small sub-triangle or sub-rectangle dull yellow marking................... 4

4 T1–T2 black, without yellow marking, T3–T5 with broader yellow bands, the band on T3 obviously interrupted medially; paraocular area yellow marking sub-rectangle; the lowest tooth on mandible acute......................................................................................... B. ( Bathanthidium s. str) fengkaiense Niu & Zhu, sp. nov.

- T1 black, T2 medially with a pair of small, stripe-like yellow markings, T3–T5 with broader yellow bands, the bands on T3–T5 entire, not interrupted medially; the lowest tooth on mandible slightly rounded........................................................................................... B. ( Bathanthidium s. str) hainanense Niu, Wu & Zhu, 2012

5 Basal zone of propodeum not distinct, with irregular, sculptured, sloping pits laterally................. 6 B. ( Manthidium)

- Basal zone of propodeum distinct laterally, with regular, shiny, nearly horizontal pits...............8 B. (Stenanthidiellum)

6 T6 yellow or with yellow fasciae basally; paraocular area black or with thin and long yellow marking.................. 7

- T6 black; paraocular area near ventral extreme with dull yellow marking or black.................................................................................................... B. (Manthidium) atriceps (Morawitz, 1890)

7 T6 with yellow fasciae basally; paraocular area with thin and long yellow marking extending along the inner margin nearly to the top of the eye..................................................... B. (Manthidium) barkamense (Wu, 1986)

- T6 yellow; paraocular area black, without yellow marking..................... B. (Manthidium) binghami (Friese, 1901)

8 Scutellum with two broad yellow markings apically.......................... B. (Stenanthidiellum) emeiense Wu, 2004

- Scutellum black...................................................................................... 9

9 Metasomal terga dull, not shiny; mandible with four teeth.................. B. (Stenanthidiellum) malaisei (Popov, 1941)

- Metasomal terga shiny; mandible with two or three teeth..................................................... 10

10 Mandible with two teeth; paraocular area near ventral extreme with small yellow marking....................................................................................... B. (Stenanthidiellum) sibiricum (Eversmann, 1852)

- Mandible with three teeth, 3 rd tooth more than 2x as far from dorsal tooth as from 2 nd tooth; paraocular area black, without yellow marking................................................... B. (Stenanthidiellum) rubopunctatum (Wu, 1993)

11 Fovea behind propodeal spiracle rounded, delimited by strong carina; T7 trilobed, median lobe longest and broad, lateral lobe short and acute; paraocular area with thin and long yellow marking extending along the inner margin to the top of the eye............................................................ B. ( Bathanthidium s. str.) bifoveolatum (Alfken, 1937)

- Fovea behind propodeal spiracle elongate, weakly delimited; T7 simple or with slightly produced median lobe (T7 of B. malaisei otherwise); paraocular area black or with different shape yellow marking.................................... 12

12 Basal zone of propodeum not distinct, with irregular, sculptured, sloping pits laterally................ 13 B. ( Manthidium)

- Basal zone of propodeum distinct laterally, with regular, shiny, nearly horizontal pits..............17 B. (Stenanthidiellum)

13 Paraocular area yellow marking thin and long, extending along the inner margin to the top or middle of the eye.......... 14

- Paraocular area yellow marking broad and short, only extending to the low margin of antennal socket................. 15

14 Mandible with two teeth; paraocular area yellow marking extending nearly to the top of the eye........................................................................................... B. (Manthidium) barkamense (Wu, 1986)

- Mandible with three teeth; paraocular area yellow marking extending to the middle of the eye................................................................................................ B. (Manthidium) bicolor (Wu, 2004)

15 T6 with yellow marking medially........................................ B. (Manthidium) binghami (Friese, 1901)

- T6 black........................................................................................... 16

16 Clypeus and with shallow and sparse punctures; apicomedian margin of clypeus nearly straight......................................................................................... B. (Manthidium) atriceps (Morawitz, 1890)

- Clypeus with deep and dense punctures; apicomedian margin of clypeus strongly extend.............................................................................................. B. (Manthidium) moganshanense (Wu, 2004)

17 Paraocular area yellow marking thin and long, extending along the inner margin to the top or middle of the eye; T7 trilobed, the median lobe long and broad, lateral lobe small and acute................... B. (Stenanthidiellum) malaisei (Popov, 1941)

- Paraocular area yellow marking broad and short, only extending to the low margin of antennal socket; T7 medially slightly produced or truncated................................................................................. 18

18 T7 medial projection triangular point with lateral shoulders.............. B. (Stenanthidiellum) rubopunctatum (Wu, 1993)

- T7 simple, truncated apically.................................... B. (Stenanthidiellum) sibiricum (Eversmann, 1852)