Echinodorus cordifolius subsp. fluitans (Fassett) R.R. Haynes & Holm-Niels. Echinodorus cordifolius subsp. fluitans (Fassett) R.R. Haynes & Holm-Niels. in Brittonia 38: 329. 1986 sec. Domínguez-Licona 2013