| Rubiaceae | |
Galium mexicanum subsp. asperrimum
| (A. Gray) Dempster | Madroño 23(7): 384 | 1976 |
| Rubiaceae | |
Galium mexicanum var. asperrimum
| (A. Gray) S.L. Welsh | Great Basin Naturalist 46(2): 260 | 1986 |
| Rubiaceae | ** |
Galium mexicanum var. asperrimum
| (A. Gray) B.L. Turner | Atlas Vasc. Pl. Texas 8 | 2003 |
| Rubiaceae | |
Galium mexicanum subsp. asperulum
| (A. Gray) Dempster | Madroño 23(7): 384 | 1976 |
| Rubiaceae | |
Galium mexicanum var. asperulum
| (A. Gray) Dempster | Brittonia 10(4): 187 | 1958 |
| Rubiaceae | |
Galium mexicanum subsp. flexicum
| Dempster | Madroño 23(7): 384–386, f. 1, 2F | 1976 |
| Rubiaceae | |
Galium mexicanum var. flexicum
| (Dempster) B.L. Turner | Atlas Vasc. Pl. Texas 8 | 2003 |
| Rubiaceae | |
Galium mexicanum var. glabratum
| Greenm. | Contr. Gray Herb. 14: 458 | 1898 |
| Rubiaceae | |
Galium mexicanum subsp. mexicanum
| | | |
| Rubiaceae | |
Galium mexicanum var. mexicanum
| | | |
| Rubiaceae | |
Galium mexicanum var. platyphyllum
| Greenm. | Contr. Gray Herb. 14: 458 | 1898 |