Mammillaria guelzowiana

Mammillaria guelzowiana is a perennial plant that grows fleshy, globose, at first solitary and then forming groups. The stems have a spherical, apically depressed, about 7 inches tall and 4-10 inches in diameter. Tubercules are conical and cylindrical. They do not contain latex. The plant has 1-6 thin central spines, needle shaped, yellowish red, 8 to 25 millimeters long. The 60-80 radial spines are long and twisted, about 15 mm long. The bell-shaped flowers are purple, more or less bright, up to 4 inches long and can reach 7 inches in diameter. The fruits are almost spherical, bright red or yellowish white, about 8 mm in length.

This species is endemic to Mexico.

Its natural habitat are hot deserts and grassy mountain tops, at an elevation of 1,300–1,700 metres (4,300–5,600 ft) above sea level.

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  Mammillaria guelzowiana at the Orto Botanico dell'Università di Genova
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  Mammillaria guelzowiana at the Prague Botanic Garden

Wikimedia Commons has media related to Mammillaria guelzowiana.

• Tropicos
• The plant list
• Cacti Guide
• Mammillaria.net
• Urs Eggli, Leonard E. Newton: Etymological Dictionary of Succulent Plant Names. Birkhäuser 2004
• Fitz Maurice, W.A. & Fitz Maurice, B. 2002. Mammillaria guelzowiana. 2006 IUCN Red List of Threatened Species. Downloaded on 22 August 2007.