| Rhachidospermum Vasey, 1890 |
| Rhachidospermum mexicanum Vasey, 1890 |
| Rhampholepis Stapf, 1917 |
| Rhaphis Lour., 1790 |
| Rhaphis (Lour.) Roberty, 1960 |
| Rhaphis halepensis (L.) Roberty, 1954 |
| Rhaphis nutans (L.) Roberty, 1954 |
| Rhaphis zizanioides (L.) Roberty, 1954 |
| Rhipidocladum McClure, 1973 |
| Rhipidocladum barbinode Ruiz-Sanchez, C.D. Tyrrell & Vigosa, 2021 |
| Rhipidocladum bartlettii (McClure) McClure, 1973 |
| Rhipidocladum harmonicum (Parodi) McClure, 1973 |
| Rhipidocladum martinezii Davidse & R.W. Pohl, 1992 |
| Rhipidocladum pittieri (Hack.) McClure, 1973 |
| Rhipidocladum racemiflorum (Steud.) McClure, 1973 |
| Rhipidocladum zoqueorum Ruiz-Sanchez & C.D. Tyrrell & Sosa, 2019 |
| Rhombolytrum Link, 1833 |
| Rhombolytrum albescens (Vasey) Nash, 1901 |
| Rhynchelytrum Nees, 1836 |
| Rhynchelytrum repens (Willd.) C.E. Hubb., 1934 |