Houstonia rubra, the red bluet, is a plant species in the Rubiaceae.Cavanilles, Antonio José. 1799. Icones et Descriptiones Plantarum 5: 48, pl. 474, f. 1. It is a small herb with white to pink to red to reddish-purple flowers, native to the southwestern United States and northern and central Mexico: Coahuila, Nuevo León, Hidalgo, Zacatecas, Guanajuato, Puebla, Sonora, Durango, Chihuahua, Arizona, New Mexico, southeastern Utah and western Texas.Southwest Environmental Information NetworkEncyclopedia of Life
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