Zea perennis, the perennial teosinte, is a true grass species in the genus Zea and a teosinte. It is one of the two perennial species in the genus Zea. The other perennial, Z. diploperennis, is the sister taxon of Z. perennis. Those two species also form a clade with Z. luxurians. Together, the three species make up the Luxuriantes section in the genus Zea. Z. perennis is the sole tetraploid in the genus and fertile hybrids with diploid Zea species are rare. Ribosomal ITS evidence suggested introgression ...