Key to the Mexican species of Kohlsia
1. Acetabular region with one long bristle........................................................................................................................ 2
- Acetabular region with more than one long bristle....................................................................................................... 3
2. Crochet with a projection ............................................................................................................................. K. fournieri
- Crochet without projection ................................................................................................................................. K. linni
3. Postantennal region with four rows of bristle............................................................................................................... 4
- Postantennal region with three rows of bristles ........................................................................................................... 5
4. In males, three antesensilial bristles, uppermost very tiny; movable process almost as long as wide .......... K. martini
- In males, two antesensilial bristles, uppermost about three times as long as ventralmost, near to the uppermost a tiny bristle; movable process at least one and a half times longer as wide ........................................... K. zyanya sp. nov.
5. With 9–10 spines in pronotal comb; four stout and long setae at the posterior margin of the movable process; sternite VIII well developed .................................................................................................................. K. ahuacatlan sp. nov.
- With more than 11 spines in pronotal comb; three stout and long setae at the posterior margin of the movable pro- cess; sternite VIII variable in shape, not hyperdeveloped ........................................................................................... 6
6. Distal arm of sternite IX bilobed bearing one bristle.................................................................................................... 7
- Distal arm of sternite IX not bilobed ............................................................................................................................ 8
7. Sternite VIII large, club-shaped process, apex bearing 5 ventromarginal bristles and two long medial bristles, dorsal margin with a hump, margin proximoventral dentate; distal arm of sternite IX with prominent ventral lobe with four stout marginal bristles and the apical lobe very markedly rounded and three very stout short setae ........... K. keenani
- Sternite VIII variable in shape, number and position of bristles, usually broad and short, with two-three apical bris- tles and three-five medial; distal arm of sternite IX with apical lobe bearing three stout marginal spiniform setae .... ....................................................................................................................................................................... K. mojica
8. Preantennal region with four rows of bristles; distal arm on sternite IX slender near to apex; apex of sternite VIII subtruncated, with two stout ventromarginal bristles and a patch of about ten very long and slender bristles; fixed