Key to females of the described Neotropical species of Gonatocerus (Lymaenon)

1 F5 and/or F6 of antenna with 1 or 2 mps ...................................................................................................................... 2

- Both F5 and F6 of antenna without mps ....................................................................................................................... 4

2(1) F6 without mps .......................................................................................................... G. (Lymaenon) litoralis (Haliday)

- F6 with 1 or 2 mps ........................................................................................................................................................ 3

3(2) Clava with 10 or 11 mps; forewing at most 3.1x as long as wide .......................... G. (Lymaenon) pratensis (Ogloblin)

- Clava with 6 mps; forewing at least 4.4x as long as wide ...................................... G. (Lymaenon) chrysis (Debauche)

4(1) Mesosoma mostly dark brown ................................................................................. G. (Lymaenon) flaviventris Dozier

- Mesosoma mostly light brown ..................................................................................... G. (Lymaenon) cubensis Dozier