[Wikipedia] Monotypic Genus, Range, Habitat: Chilopsis is a monotypic genus of flowering plants containing the single species Chilopsis linearis. It is known commonly as desert willow[4] or desert-willow[3] because of its willow-like leaves, but it is not a true willow – being instead a member of the catalpa family. It is a shrub or tree native to the southwestern United States and Mexico. It is commonly seen in washes and along riverbanks. (link added by Mary Ann Machi)