Key to the species of the genus Gonioctena in the Korean Peninsula
(modified from Cho & Lee 2008)
1. Posterior angles of pronotum with setigerous pores.................................................................................................... 2
- Posterior angles of pronotum without setigerous pores (Subgenus Brachyphytodecta) ......... G. fulva (Motschulsky)
2. Anterior angles of pronotum with setigerous pores (Subgenus Sinomela) ................................... G. aeneipennis Baly
- Anterior angles of pronotum without setigerous pores (Subgenus Gonioctena) ......................................................... 3
3. Antennae fully reaching the elytral humeri with seventh to tenth segments elongate, each 2–2.3 times longer than wide ........................................................................................................................................ G. gracilicornis (Kraatz)
- Antennae never reaching the elytral humeri with seventh to tenth segments distinctly widened, each nearly as long as wide ......................................................................................................................................................................... 4
4. Ventral surface entirely or largely reddish to yellowish brown .................................................................................... 5
- Ventral surface entirely or largely black ..................................................................................................................... 6
5. Elytra with black spots.......................................................................................... G. koryeoensis Cho & Lee, sp. nov.
- Elytra without black spots................................................................................................................ G. kamiyai Kimoto
6. Femora and tibiae entirely reddish brown; pronotum and elytra without distinct black spots, rarely with obscure black spots..................................................................................................................................................................... 7
- Femora and tibiae at least partly black, if entirely reddish brown, pronotum or elytra with distinct black spots ....... 8
7. Head almost entirely black; antennae yellowish brown with distal four to five segments piceous ............................... ........................................................................................................................... G. jacobsoni (Ogloblin et Medvedev)
- Head yellowish brown with posterior portion black; antennae entirely yellowish brown .............. G. suwai Takizawa
8. Pronotum with a pair of triangular basal black markings; elytra reddish brown with five pairs of black spots; elytral suture black except for basal 1/4...................................................................................................... G. laeta Medvedev
- Without above combination of characteristics............................................................................................................. 9
9. Antennae yellowish brown with distal four to five segments each apically darkened ............ G. viminalis (Linnaeus)
- Antennae yellowish brown to brown with distal four to five segments black........................................................... 10
10. Elytra partly or entirely reddish brown, never entirely black, with or without black spots; tibiae black with median and apical portions largely reddish brown .................................................................................. G. coreana (Bechyné)
- Elytra entirely black or reddish brown, without black spots; tibiae entirely black, sometimes with apical portion partly dark brown ............................................................................................................................ G. sibirica (Weise)