| Dahlia purpusii Brandegee, 1914 |
| Dahlia rudis P.D. Sørensen, 1969 |
| Dahlia rupicola P.D. Sørensen, 1969 |
| Dahlia scapigera (A. Dietr.) Knowles & Westc., 1840 |
| Dahlia scapigera f. australis Sherff, 1947 |
| Dahlia scapigera f. purpurea Sherff, 1947 |
| Dahlia scapigera f. scapigera (A. Dietr.) Knowles & Westc., 1840 |
| Dahlia scapigera f. serratior Sherff, 1947 |
| Dahlia scapigera f. typica Sherff, 1947 |
| Dahlia scapigera var. arsenei Sherff, 1946 |
| Dahlia scapigera var. australis Sherff, 1947 |
| Dahlia scapigera var. liebmannii Sherff, 1947 |
| Dahlia scapigera var. scapigera (A. Dietr.) Knowles & Westc., 1840 |
| Dahlia scapigera var. typica Sherff, 1947 |
| Dahlia scapigeroides Sherff, 1947 |
| Dahlia scapigeroides var. apiculata Sherff, 1947 |
| Dahlia sherffii P.D. Sørensen, 1969 |
| Dahlia sorensenii H.V. Hansen & Hjert., 1997 |
| Dahlia spectabilis Saar & P.D. Sørensen, 2002 |
| Dahlia sublignosa (P.D. Sørensen) Saar & P.D. Sørensen, 2006 |