Castilleja indivisa, commonly known as Texas Indian paintbrush or entireleaf Indian paintbrush, is a hemiparasitic annual wildflower native to Texas, Louisiana, and Oklahoma in the United States. Each plant typically grows 30–45 cm (12–18 in) in height. The leaves are long and stalkless. The roots grow until they reach the roots of other plants, mainly grasses, and then penetrate the roots of the "host" plant to obtain a portion of their needed nutrients (known as semi- or hemiparasitism).