Thelocactus setispinus

The genus name "Theloocactus" derives from the Greek word "Thelo" (wart or nipple) referred to the ribs with closely spaced nipples, while the species name "setispinus" comes from the Latin “seta” meaning “bristle” and “spina” meaning “thorn, spine”.[3][4]

Thelocactus setispinus is globe-shaped to short cylindrical cactus about 8 inches (20 cm) to 12 inches (30 cm) wide and up to 60 centimetres (24 in) tall. The 12 to 15 radial spines are needle-shaped, bright, brown or white and up to 4 inches (10 cm) long. The 1 to 3 central spines are longer and stronger, straight and curved like a hook at the tip. The flowers are orange, dark yellow, magenta, or violet[5] with a red center, about 7 inches (18 cm) long. This cactus blooms in late summer. The fruits are red, round or elliptical, a little scaly, about 8 millimetres (0.31 in) to 10 millimetres (0.39 in).[6]

This species is widespread in the southern United States in the State of Texas and the Mexican states of Coahuila, Nuevo León and Tamaulipas. This species has spread throughout the world as an ornamental plant.[7]

Its natural habitat is arid deserts, distributed widely but has a scattered population.[8] It usually grows in black or clay soils on coastal lowlands under mesquite scrubs, at an elevation of about 0–550 metres (0–1,804 ft) above sea level.[9]

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  Close-up on a flower of Thelocactus setispinus