Ayenia limitaris is a rare North American species of flowering plant in the mallow family known by the common names Rio Grande ayenia, Texas ayenia, and Tamaulipan kidneypetal. It is native to an area straddling the Rio Grande in Mexico and the United States. Today it is known from far southern Texas and far northern sections of the Mexican states of Coahuila and Tamaulipas. It has become rare because most of its habitat has been degraded or destroyed. There are perhaps four populations remaining in Texas and two in Mexico, for a total of 1000 individual plants at most. It is a federally listed endangered species of the United States.