Key to females of Oideterus

1 Elytra proportionally short, not entirely covering the fourth abdominal segment, strongly dehiscent along suture just below scutellum ........................................................................................................................................................... 2

- Elytra proportionally long, totally covering the fourth abdominal segment, slightly dehiscent along suture, usually more distinctly at distal half.......................................................................................................................................... 3

2(1) Head and prothorax totally black. Colombia ...................................................................... O. lobicollis (Bates, 1875)

- Head and prothorax not black, with distinct light areas. Ecuador .............................. O. elegans (Waterhouse, 1880)

3(1) Antennae not reaching elytral apex ............................................................................................................................. 4

- Antennae reaching elytral apex. Ecuador .................................................................................. O. inaequalis sp. nov.

4(3) Scape and femora coarsely, abundantly punctate; outer margin of elytra somewhat enlarged about middle. Panama. ...................................................................................................................................... O. magnificus (Galileo, 1987)

- Scape and femora finely, sparsely punctate; outer margin of elytra not enlarged at middle, more or less convergent from base to apex or subparallel from base to about distal third .................................................................................. 5

5(4) Projections of antennomeres VII-X long (apex of projection surpasses middle of next antennomere); body wide. Ecuador ........................................................................................................................ O. dichotomus (Galileo, 1987)

- Projections of antennomeres VII-X short (apex of projection not reaching middle of next antennomere); body slen- der. Colombia ..................................................................................................................... O. pallidus (Galileo, 1987)