The stems are cylindrical and usually measure up to 10 centimeters tall, but known to reach 30.

There are two main population areas in Arizona, one in the Avra Valley and Saguaro National Park and one on the Tohono O'odham Indian Reservation.

[2] This species was abundant in the Avra Valley up until the 1930s until a freeze which decimated the population.

[2] This species was first described as Mammillaria thornberi in 1902 by Charles Russell Orcutt.

[5] Peter B. Breslin and Lucas C. Majure placed the species in the genus Cochemiea in 2021[6]