Oxytheca is a genus of plants in the family Polygonaceae with seven species found in dry and temperate parts of the Americas. The taxonomy of this genus is in flux, with some species often listed under tentative new names. Species include: \n* Oxytheca dendroidea \n* Oxytheca parishii = Acanthoscyphus parishii \n* Oxytheca perfoliata \n* Oxytheca watsonii