Thelocactus setispinus

Thelocactus setispinus, commonly known as miniature barrel cactus^[2] or hedgehog cactus, is a species of cactus in the family Cactaceae.

Thelocactus setispinus
At the Orto Botanico dell'Università di Genova
Conservation status
Least Concern  (IUCN 3.1)[1]
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Order:	Caryophyllales
Family:	Cactaceae
Subfamily:	Cactoideae
Genus:	Thelocactus
Species:	T. setispinus
Binomial name
Thelocactus setispinus (Engelm.) E.F.Anderson
Synonyms
Hamatocactus setispinus (Engelm.) Britton & Rose Ferocactus setispinus (Engelm.) LDBenson.

Description

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^[3] with a red center, about 7 inches (18 cm) long. This cactus blooms in late spring to summer. The fruits are red, round or elliptical, a little scaly, about 8 millimetres (0.31 in) to 10 millimetres (0.39 in).^[4]

Distribution

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.^[5] Its natural habitat is arid deserts, distributed widely but has a scattered population.^[6] 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.^[7] Plants are found growing along Astrophytum asterias, Mammillaria heyderi, Echinocereus stramineus, Echinocereus poselgeri and Homalocephala texensis^[8]

• 
  Close-up on a flower of Thelocactus setispinus.

Taxonomy

In 1845 George Engelmann first described the plant as Echinocactus 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".^[9][10] Edward Frederick Anderson placed the species in the genus Thelocactus in 1987.^[11]