| Mesadenus minutiflorus (A. Rich. & Galeotti) Schltr., 1920 |
| Mesadenus polyanthus (Rchb. f.) Schltr., 1920 |
| Mesadenus tenuissimus (L.O. Williams) Garay, 1982 |
| Mesicera Raf., 1825 |
| Mesicera michauxii (Nutt.) Raf., 1837 |
| Mesicera quinqueseta (Michx.) Raf., 1825 |
| Mesoglossum Halb., 1982 |
| Mesoglossum londesboroughianum (Rchb. f.) Halb., 1982 |
| Mexicoa Garay, 1974 |
| Mexicoa ghiesbreghtiana (A. Rich. & Galeotti) Garay, 1974 |
| Mexipedium V.A. Albert & M.W. Chase, 1992 |
| Mexipedium xerophyticum (Soto Arenas, Salazar & Hágsater) V.A. Albert & M.W. Chase, 1992 |
| Microchilus C. Presl, 1827 |
| Microchilus lunifer (Schltr.) Ormerod, 2002 |
| Microchilus mexicanus (Ames) Ormerod, 2002 |
| Microchilus venustulus (Ames) E.C. Smidt & M.W. Chase, 2021 |
| Microchilus vesicifer (Rchb. f.) Ormerod, 2002 |
| Microepidendrum Brieger ex W.E. Higgins, 2002 |
| Microepidendrum subulatifolium (A. Rich. & Galeotti) W.E. Higgins, 2002 |
| Microstylis (Nutt.) Eaton, 1822 |