| Koanophyllon palmeri var. palmeri (A. Gray) R.M. King & H. Rob., 1971 |
| Koanophyllon palmeri var. tonsum B.L. Rob., 1906 |
| Koanophyllon peninsulare (Brandegee) B.L. Turner, 1998 |
| Koanophyllon phanioides (Urb. & Ekman) R.M. King & H. Rob., 1975 |
| Koanophyllon pittieri (Klatt) R.M. King & H. Rob., 1971 |
| Koanophyllon pochutlana B.L. Turner, 2012 |
| Koanophyllon potosinum Rzed., 2018 |
| Koanophyllon pseudoperfoliata (Sch. Bip. ex Klatt) R.M. King & H. Rob., 1971 |
| Koanophyllon ravenii R.M. King & H. Rob., 1971 |
| Koanophyllon revealii B.L. Turner, 2009 |
| Koanophyllon reyrobinsonii B.L. Turner, 1983 |
| Koanophyllon richardsonii B.L. Turner, 1983 |
| Koanophyllon rzedowskii B.L. Turner, 1987 |
| Koanophyllon sinaloensis B.L. Turner, 1987 |
| Koanophyllon solidaginifolium (A. Gray) R.M. King & H. Rob., 1971 |
| Koanophyllon solidaginoides (Kunth) R.M. King & H. Rob., 1971 |
| Koanophyllon sorensenii R.M. King & H. Rob., 1972 |
| Koanophyllon standleyi (B.L. Rob.) R.M. King & H. Rob., 1971 |
| Koanophyllon tripartitum B.L. Turner, 1987 |
| Krigia Schreb., 1791 |