| Orchiodes Kuntze, 1891 |
| Orchiodes decipiens (Lindl.) Kuntze, 1891 |
| Orchis L., 1753 |
| Orchis dilatata Pursh, 1813 |
| Orchis entomantha Lex., 1825 |
| Orchis michauxii Wood, 1870 |
| Orchis monorrhiza Sw., 1788 |
| Orchis pauciflora Sessé & Moc., 1894 |
| Orchis quinqueseta Michx., 1803 |
| Orchis repens (Nutt.) Raf., 1825 |
| Orchis strateumatica L., 1753 |
| Ornithidium Salisb. ex R. Br., 1813 |
| Ornithidium densum (Lindl.) Rchb. f., 1855 |
| Ornithidium hagsaterianum (Soto Arenas) Senghas, 2001 |
| Ornithidium simulans Ames & C. Schweinf., 1930 |
| Ornithidium tonsoniae (Soto Arenas) Senghas, 2001 |
| Ornithocephalus Hook., 1824 |
| Ornithocephalus bicornis Lindl., 1846 |
| Ornithocephalus biloborostratus Salazar & R. González, 1990 |
| Ornithocephalus gladiatus Hook., 1824 |