Rubiaceae | |
Houstonia acerosa var. acerosa
| | | |
Rubiaceae | |
Houstonia acerosa subsp. polypremoides
| (A. Gray) Terrell | Brittonia 31(1): 168 | 1979 |
Rubiaceae | |
Houstonia acerosa var. polypremoides
| (A. Gray) Terrell | Sida 19(4): 916 | 2001 |
Rubiaceae | |
Houstonia acerosa var. tamaulipana
| (B.L. Turner) Terrell | Sida 19(4): 916–918 | 2001 |