Exacum affine

Exacum affine (syn. Exacum socotranum, Exacum gracilipes) known commercially as the Persian violet, is a species of plant in the family Gentianaceae. It is endemic to Socotra, part of Yemen, though its popularity and cultivation around the world have made it an occasional greenhouse weed. Its natural habitat is rocky areas. A small herbaceous biennial plant with dark green, ovate leaves. The small purple flowers have a yellow centre with fragrance. If Exacum socotranum is considered a distinct species separate from Exacum affine the former is critically endangered, being restricted to a few localities threatened by urban development.