| Guardiola mexicana var. mexicana Kunth, 1807 |
| Guardiola odontophylla B.L. Rob., 1899 |
| Guardiola palmeri B.L. Rob., 1907 |
| Guardiola pappifera Paul G. Wilson, 1958 |
| Guardiola platyphylla A. Gray, 1853 |
| Guardiola rosei B.L. Rob., 1899 |
| Guardiola rotundiflora B.L. Rob., 1894 |
| Guardiola rotundifolia B.L. Rob., 1894 |
| Guardiola stenodonta S.F. Blake, 1924 |
| Guardiola thompsonii Van Faasen, 1976 |
| Guardiola tulocarpus A. Gray, 1852 |
| Guardiola tulocarpus var. angustifolia A. Gray, 1887 |
| Guardiola tulocarpus var. arguta A. Gray, 1886 |
| Guardiolinae H. Rob., 1978 |
| Guizotia Cass., 1829 |
| Guizotia abyssinica (L. f.) Cass., 1829 |
| Gundlachia A. Gray, 1880 |
| Gundlachia diffusa (Benth.) Urbatsch & R.P. Roberts, 2004 |
| Gundlachia riskindii (B.L. Turner & G. Langford) Urbatsch & R.P. Roberts, 2004 |
| Gundlachia triantha (S.F. Blake) Urbatsch & R.P. Roberts, 2004 |