| Acanthocalycium andreaeanum (Backeb.) Donald |
Synonym |
 |
WCSP (in review) |
| Acanthocalycium aurantiacum Rausch |
Synonym |
 |
WCSP (in review) |
| Acanthocalycium brevispinum F.Ritter |
Synonym |
 |
WCSP (in review) |
| Acanthocalycium catamarcense F.Ritter |
Synonym |
 |
WCSP (in review) |
| Acanthocalycium chionanthum (Speg.) Backeb. |
Synonym |
 |
WCSP (in review) |
| Acanthocalycium ferrarii Rausch |
Unresolved |
 |
WCSP (in review) |
| Acanthocalycium formosanum var. albispinum (Weber ex Schelle) Y. Itô |
Unresolved |
 |
TRO |
| Acanthocalycium formosum (Pfeiff.) Backeb. |
Synonym |
 |
WCSP (in review) |
| Acanthocalycium glaucum F.Ritter |
Synonym |
 |
WCSP (in review) |
| Acanthocalycium griseum Backeb. |
Synonym |
 |
WCSP (in review) |
| Acanthocalycium hyalacanthum (Speg.) Backeb. |
Unresolved |
 |
WCSP (in review) |
| Acanthocalycium klimpelianum (Weidlich & Werderm.) Backeb. |
Accepted |
 |
WCSP (in review) |
| Acanthocalycium klimpelianum var. macranthum (Rausch) J.G.Lamb. |
Synonym |
 |
WCSP (in review) |
| Acanthocalycium oreopepon (Speg.) Backeb. |
Synonym |
 |
WCSP (in review) |
| Acanthocalycium oreopogon Backeb. |
Unresolved |
 |
TRO |
| Acanthocalycium peitscherianum Backeb. |
Synonym |
 |
WCSP (in review) |
| Acanthocalycium spiniflorum (K.Schum.) Backeb. |
Accepted |
 |
WCSP (in review) |
| Acanthocalycium spiniflorum f. klimpelianum (Weidlich & Werderm.) Donald |
Synonym |
 |
TRO |
| Acanthocalycium spiniflorum var. klimpelianum (Weidlich & Werderm.) Donald |
Synonym |
 |
TRO |
| Acanthocalycium thionanthum (Speg.) Backeb. |
Synonym |
 |
WCSP (in review) |
| Acanthocalycium thionanthum var. aurantiacum (Rausch) Donald |
Synonym |
 |
TRO |
| Acanthocalycium thionanthum var. brevispinum (F. Ritter) Donald |
Synonym |
 |
TRO |
| Acanthocalycium thionanthum var. glaucum (F. Ritter) Donald |
Synonym |
 |
TRO |
| Acanthocalycium variiflorum Backeb. |
Unresolved |
 |
WCSP (in review) |
| Acanthocalycium violaceum (Werderm.) Backeb. |
Synonym |
 |
WCSP (in review) |