Thelocactus conothelos is a species of cactus endemic to Mexico.

[1] Thelocactus conothelos is a solitary, spherical cactus, growing 7 to 18 cm (2.8 to 7.1 in) in height and diameter.

Its ribs are indistinct, with conical warts that are light green at the base and squared.

The large, spreading flowers range from 4.5 to 6 cm (1.8 to 2.4 in) wide and vary in color from white to magenta.

[2] Accepted subspecies:[1] This species is native to Tamaulipas, Nuevo León, and San Luis Potosí, Mexico at elevations between 1200 and 2200 meters growing in shrubland and limestone slopes.