Thelocactus hexaedrophorus ssp. hexaedrophorus, type form:
Thelocactus hexaedrophorus ssp. hexaedrophorus HO 61:
Thelocactus hexaedrophorus ssp. hexaedrophorus SB 291:
Thelocactus hexaedrophorus ssp. hexaedrophorus var. droegeanus:
Thelocactus hexaedrophorus ssp. hexaedrophorus var. fossulatus SB 892:
Thelocactus hexaedrophorus ssp. hexaedrophorus var. major HK 1609:
Thelocactus hexaedrophorus ssp. lloydii: