Hainardia is a genus of coastal plants in the grass family, native to the Mediterranean Basin. The only known species is Hainardia cylindrica, known by several common names, including barbgrass, one-glumed hard-grass, and thintail. It is native to the Mediterranean and to nearby regions from Madeira and the Canary Islands east to Crimea and Iran. It ia also reportedly naturalized in coastal regions in scattered locales in Australia, New Zealand, the United States (CA OR TX LA SC), Baja California, and temperate South America (Brazil, Uruguay, Argentina, Chile).