Obregonia is among the most famous of all cacti for is unique artichoke-shaped stem. It is the only representative of its monospecific genus and is related to Ariocarpus. It grows almost always as a solitary plant levelled with the ground, with the sunk and woolly apex. It is considered an intermediate form between Ariocarpus and Lophophora.
Stem are solitary, globular-squashed resembling an inverted pine cone with a woolly centre, it grows up to 15 (or more) cm in diameter and is greyish green to dark green.