 Amaranthus brownii is an annual herb in the Amaranthaceae family . The plant is found only on the small island of Nihoa in the Northwestern Hawaiian Islands , growing on rocky outcrops at altitudes of 120 – 215 m ( 394 – 705 ft ) . It is one of nine species of Amaranthus in the Hawaiian Islands , but the only endemic Hawaiian species of the genus . It was first discovered during the Tanager Expedition in 1923 by botanist Edward Leonard Caum . A. brownii differs from other Hawaiian species of Amaranthus with its spineless leaf axils , linear leaves , and indehiscent fruits . 
