| Nominal Species (n = 4) | Present allocation (n = 4) | Ref. |
|---|---|---|
| Acauloides ammisatum Bouillon, 1965 | Acauloides ammisatum | 8278 |
| Hataia parva Hirai & Yamada, 1965 | Hataia parva | 1663 |
| Acaulis primarius Stimpson, 1854 | Acaulis primarius | 19 |
| Cryptohydra thieli Thomas, Edwards & Higgins, 1995 | Cryptohydra thieli | 8278 |