| Hoffmannia wilsonii Standl., 1940 |
| Houstonia L., 1753 |
| Houstonia acerosa (A. Gray) Benth. & Hook. f., 1873 |
| Houstonia acerosa subsp. tamaulipana (B.L. Turner) Borhidi, 2012 |
| Houstonia acerosa var. polypremoides (A. Gray) Terrell, 2001 |
| Houstonia angustifolia Michx., 1803 |
| Houstonia angustifolia var. scabra S. Watson, 1883 |
| Houstonia asperuloides (Benth.) A. Gray, 1860 |
| Houstonia bouvardioides (Seem.) Benth. & Hook. f., 1873 |
| Houstonia coccinea Andr., 1800 |
| Houstonia fruticosa Rose, 1891 |
| Houstonia gracilis Brandegee, 1907 |
| Houstonia humifusa A. Gray, 1859 |
| Houstonia longiflora (Cav.) A. Gray, 1860 |
| Houstonia longipes S. Watson, 1883 |
| Houstonia macvaughii (Terrell) Govaerts ex Borhidi, 2012 |
| Houstonia mucronata (Benth.) B.L. Rob., 1910 |
| Houstonia mullerae (Fosberg) Terrell, 1979 |
| Houstonia palmeri A. Gray, 1882 |
| Houstonia palmeri subsp. muzquizana (B.L. Turner) Borhidi, 2012 |