Gymnocalycium denudatum

Gymnocalycium denudatum is a species of Gymnocalycium from Brazil to Argentina.^[2]

Gymnocalycium denudatum
Conservation status
Endangered  (IUCN 3.1)[1]
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Order:	Caryophyllales
Family:	Cactaceae
Subfamily:	Cactoideae
Genus:	Gymnocalycium
Species:	G. denudatum
Binomial name
Gymnocalycium denudatum (Link & Otto) Pfeiff. ex Mittler 1845
Synonyms
Echinocactus denudatus Link & Otto 1828 Echinocactus denudatus var. typica K.Schum. 1890 Cereus denudatus Pfeiff. 1837 Echinocactus denudatus var. leheideliana F.Haage 1898 Echinocactus denudatus f. octogonus (K.Schum.) Schelle 1907 Echinocactus denudatus var. octogonus K.Schum. 1890 Echinocactus megalothelon Sencke ex K.Schum. 1898 Echinopsis denudatus (Pfeiff.) Bosse 1860 Gymnocalycium denudatum subsp. necopinum Prestlé 2004 Gymnocalycium megalothelon (Sencke ex K.Schum.) Britton & Rose 1922 Gymnocalycium megalothelon subsp. prestleanum H.Till 2005

Description

Gymnocalycium denudatum is a solitary cactus with shiny, dark green, depressed spherical stems, 2–3 cm tall and 6–8 cm wide. It has 5–8 flat, minimally bumpy ribs with sparse areoles. Each areole bears 3–5 slightly twisted, whitish-yellow spines, 1–1.5 cm long, lying close to the stem. The plant produces pure white, glossy flowers up to 5 cm long and 7 cm wide, and elongated green fruits. The species is highly variable.^[3][4]

• 
  Pink flower form
• 
  Plant
• 
  White flower form
• 
  Areole and spine

Distribution

Native to Brazil (Rio Grande do Sul), Uruguay, Argentina (Misiones, Corrientes), and likely Paraguay, it grows at altitudes up to 500 meters.^[5]

• 
  G. denudatum growing in Rio Grande do Sul

Taxonomy

Originally described as Echinocactus denudatus by Heinrich Friedrich Link and Christoph Friedrich Otto in 1828, Ludwig Mittler reassigned it to the genus Gymnocalycium in 1844. The epithet denudatum means "naked."