The genus Rhodophiala in the Amaryllis Family (Amaryllidaceae) is native to Chile and Argentina in South America. It belongs to the tribe Hippeastreae, and the Rhodophiala are related to Sprekelia, Zephyranthes, and Habranthus, all in the same tribe. They are herbaceous perennial bulbs. The flowers are borne in an umbel at the top of the peduncle or stalk.

Closely related are the rain lilies, Zephyranthes and Habranthus and the genus Cooperia, which is submerged into Zephyranthes by some taxonomists. These genera are currently being studied using DNA sequencing. Marked revisions of the assignments of some of the species in these genera can be expected. See: Amaryllid Phylogeny

Some species of Zephyranthes:

• Rhodophiala advena is native to Chile. The flowers are bright red.
  
    
  
• Rhodophiala bagnoldii grows in Argentina and Chile. The flowers are yellow, and appear in summer.
  
    
  
• Rhodophiala bifida is the common Oxblood Lily in gardens in the Southern United States as the sterile triploid form. The fertile wild form, diploid, is from Argentina and Uruguay. The flowers of both forms are deep vermilion red and appear in late summer in cultivation in the Northern Hemisphere.
  
    
  
• Rhodophiala laeta is found in Chile in the coastal mountains. Flowers are red or purple, blooming in spring.
  
    
  

Other Sources of Information

Bulbs for Warm Climates, Thad M. Howard, University of Texas Press, Austin (2001).
Bulbs, Revised Edition, John E. Bryan, Timber Press, Portland (2002).
Bulbs of North America, Jane McGary, Editor, Timber Press and North American Rock Garden Society, Portland (2001).
RHS Manual of Bulbs, John Bryan and Mark Griffiths, Eds., Timber Press, Portland (1995).

For a list of species names, see the Missouri Botanic Garden's Tropicos On-Line Database at http://mobot.mobot.org/W3T/Search/vast.html