Thelocactus is a genus in the cactus family, Cactaceae. Members of the genus are native to the arid lands of Central and Northern Mexico.
Thelocactus species are globe-shaped, short and cylindrical. They are small cacti, although there are one or two species which, while only about 15 cm high, can be 25 cm in diameter; for example, T. nidulans. Thelocactus species are generally solitary, but some varieties will cluster in groups.
The ribs on Thelocactus species are very clearly marked and are sometimes ...