Erythrostemon is a genus of flowering plants in the legume family Fabaceae, placed in the order Fabales. The genus comprises around 30 species of shrubs and small trees native to tropical and subtropical America, ranging from the southern United States through Mexico and Central America into South America.
Members of the genus were formerly treated within the large, broadly defined genus Caesalpinia, and were reclassified into Erythrostemon following a comprehensive molecular phylogenetic revision by Gagnon and Lewis. The transfer of species reflects a refined understanding of generic limits within the tribe Caesalpinieae. The name Erythrostemon derives from Greek, referring to the red stamens that characterise many species in the group.
Plants in this genus are typically thorny or unarmed shrubs with pinnate or bipinnate leaves and showy flowers bearing conspicuous, often scarlet or yellow, exserted stamens. The best-known member is Erythrostemon gilliesii (bird of paradise or bird of paradise bush), widely cultivated as an ornamental in warm climates for its bright yellow petals and long red stamens. Erythrostemon mexicanus (Mexican holdback) occurs in southernmost Texas and Mexico. Other species such as E. coccineus, E. palmeri, and E. pannosus are restricted to Mexico.
Distribution
The genus is native to tropical and subtropical America, with species distributed across Mexico, Central America, and South America. Erythrostemon mexicanus extends into southernmost Texas, representing the genus's northern limit in the United States.
Taxonomy Notes
Erythrostemon was reinstated as a distinct genus following a molecular phylogenetic revision of Caesalpinia and related genera by Gagnon and Lewis, who transferred numerous Caesalpinia species into Erythrostemon and several other segregate genera. The genus belongs to the tribe Caesalpinieae within Fabaceae (order Fabales).
