| Nominal Species (n = 27) | Present allocation (n = 24) | Ref. |
|---|---|---|
| Synthecium brucei Vervoort & Watson, 2003 | Synthecium brucei | 8278 |
| Synthecium campylocarpum Allman, 1888 | Synthecium campylocarpum | 8278 |
| Synthecium carinatum Totton, 1930 | Synthecium carinatum | 19 |
| Synthecium chilense Hartlaub, 1905 | Synthecium protectum | 3477 |
| Hincksella corrugata Millard, 1958 | Hincksella corrugata | 8278 |
| Synthecium dentigerum Jarvis, 1922 | Synthecium dentigerum | 8278 |
| Synthecium elegans Allman, 1872 | Synthecium elegans | 19 |
| Synthecium flabellum Hargitt, 1924 | Synthecium flabellum | 8278 |
| Synthecium gordoni Vervoort & Watson, 2003 | Synthecium gordoni | 8278 |
| Synthecium gracile Fraser, 1937 | Hincksella cylindrica | 19 |
| Synthecium hians Millard, 1957 | Synthecium hians | 8278 |
| Hincksella immersa Galea, 2019 | Hincksella immersa | 3477 |
| Hincksella indiana Millard, 1967 | Hincksella indiana | 8278 |
| Synthecium longithecum Totton, 1930 | Synthecium longithecum | 19 |
| Synthecium megathecum Billard, 1925 | Synthecium megathecum | 8278 |
| Synthecium nanum Fraser, 1943 | Synthecium tubithecum | 75097 |
| Thuiaria polycarpa Kirchenpauer, 1884 | Parathuiaria polycarpa | 93029 |
| Synthecium protectum Jäderholm, 1903 | Synthecium protectum | 3477 |
| Synthecium rectum Nutting, 1904 | Synthecium tubithecum | 75097 |
| Synthecium rigidum Fraser, 1938 | Synthecium rigidum | 8278 |
| Synthecium robustum Nutting, 1904 | Synthecium protectum | 19 |
| Synthecium samauense Billard, 1925 | Synthecium samauense | |
| Hincksella sibogae Billard, 1918 | Hincksella sibogae | 8278 |
| Synthecium singulare Billard, 1925 | Synthecium singulare | 8278 |
| Synthecium symmetricum Fraser, 1938 | Synthecium symmetricum | 19 |
| Synthecium tottoni Ralph, 1958 | Synthecium tottoni | 19 |
| Synthecium tubiger Jarvis, 1922 | Synthecium tubiger | 8278 |