This genus of cacti, distributed in the South-eastern United States and Northeast Mexico, grows on grass and in the shade of shrubs, in arid regions, on alluvial limestone sandy or rocky soils, at altitudes ranging between 800 and 2,300 metres above sea level. A genus of usually solitary globose to cylindrical plants, with bluish-green epidermis and hooked central spines, which are often very long. Glandulicactus is the only genus of Cactoideae in the flora with strongly hooked, abaxial radial spines, conspicuous even on immature plants two centimetres in diameter. Flowers can be orange, red brown or dark brown. The extra-floral nectaries located in the tubercles give the name to these cacti, which, according to some authors, should be lumped into Sclerocactus. They need both winter and summer rest.
