| Cheirinia nivalis (Greene) Rydb., 1912 |
| Cheirinia nivalis var. radicata (Rydb.) Cockerell, 1913 |
| Cheirinia oblanceolata Rydb., 1912 |
| Cheirinia radicata (Rydb.) Rydb., 1912 |
| Cheirinia wheeleri (Rothr.) Rydb., 1912 |
| Chorispermum W.T. Aiton, 1812 |
| Chorispora R. Br. ex DC., 1821 |
| Chorispora tenella (Pall.) DC., 1821 |
| Chorisporeae C.A. Mey., 1831 |
| Cibotarium O.E. Schulz, 1933 |
| Cibotarium divaricatum Rollins, 1941 |
| Cibotarium divaricatum var. compressum Rollins, 1941 |
| Cibotarium fruticulosum Rollins, 1941 |
| Cibotarium macropetalum Rollins, 1941 |
| Cibotarium macrum (Standl.) Rollins, 1941 |
| Cibotarium microcarpum Rollins, 1957 |
| Cibotarium stellatum (S. Watson) O.E. Schulz, 1933 |
| Clandestinaria (DC.) Spach, 1838 |
| Clypeola L., 1753 |
| Clypeola maritima L., 1753 |