The monstrous form of a succulent plant is highly sought after by collectors from all over the world due to the strong deformations that the specimen undergoes compared to the "normal" one, which make it absolutely unique and never the same as other plants. In its normal form Thelocactus rinconensis is a greyish-green solitary cactus with a globular stem, slightly depressed at the top, covered with a characteristic woolly down. It has very pronounced tubercles and its spines are long, straight, generally gray-black and paler at the top.