| Stenosiphon Spach, 1835 |
| Stenosiphon linifolius (Nutt. ex E. James) Heynh., 1840 |
| Stipogaura (P.H. Raven & D.P. Greg.) W.L. Wagner & Hoch, 2007 |
| Tetrapteron (Munz) W.L. Wagner & Hoch, 2007 |
| Tetrapteron graciliflorum (Hook. & Arn.) W.L. Wagner & Hoch, 2007 |
| Xanthocoryne W.L. Wagner & Hoch, 2007 |
| Xylonagra Donn. Sm. & Rose, 1913 |
| Xylonagra arborea (Kellogg) Donn. Sm. & Rose, 1913 |
| Xylopleurum Spach, 1835 |
| Xylopleurum deserticola Loes., 1913 |
| Xylopleurum roseum (Aiton) Raim., 1893 |
| Xylopleurum tetrapterum (Cav.) Raim., 1893 |
| Zauschneria C. Presl, 1831 |
| Zauschneria (Presl) P.H. Raven, 1977 |
| Zauschneria californica C. Presl, 1831 |