Turbinicarpus valdezianus

Turbinicarpus valdezianus is a very small cactus of northern Mexico, placed in the family Cactaceae. It is regarded as one of the smallest and slowest-growing members of its genus. The plant is usually solitary, though it can occasionally form clumps. Young plants are spherical, and with age the stem becomes cylindrical with a narrower base and short tubercles arranged in a spiral. About half of the plant lies underground, held in place by a substantial taproot, and the visible part typically reaches three to five centimetres in height and one to two centimetres across. Its body is hidden beneath twenty-five to thirty dense, feathery white spines, each about half a millimetre long, that lie flat around the areoles and completely cover the apex. In spring it bears one to five daytime flowers at the top of the stem, coloured pinkish-white to bright pink with darker magenta or reddish-brown midveins. It grows in scattered small populations in the Chihuahuan Desert and the Meseta Central matorral, from near Saltillo in Coahuila almost to Matehuala in San Luis Potosí, at 1,400 to 1,600 metres, and is threatened by habitat loss.