| Ravnia triflora Oerst., 1853 |
| Relbunium (Endl.) Benth. & Hook. f., 1873 |
| Relbunium aschenbornii (Schauer) Hemsl., 1881 |
| Relbunium hypocarpium (L.) Hemsl., 1881 |
| Relbunium laevigatum (DC.) Hemsl., 1881 |
| Relbunium microphyllum (A. Gray) Hemsl., 1881 |
| Relbunium polyplocum Hemsl., 1880 |
| Renistipula Borhidi, 2004 |
| Renistipula galeottii (Standl.) Borhidi, 2004 |
| Renistipula izabalensis (Standl. & Steyerm.) Borhidi, 2004 |
| Resinanthus (Borhidi) Borhidi, 2007 |
| Resinanthus aromaticus (Cast.-Campos & Lorence) Borhidi, 2007 |
| Richardia L., 1753 |
| Richardia adscendens (Pav. ex DC.) Steud., 1841 |
| Richardia africana Kunth, 1815 |
| Richardia brasiliensis Gomes, 1801 |
| Richardia elliottiana (H. Knight) W. Watson, 1892 |
| Richardia gandarae Rzed., 1983 |
| Richardia haenkeana (DC.) Steud., 1841 |
| Richardia humistrata (Cham. & Schltdl.) Steud., 1841 |