Not every plant called an Iris is in the Genus Iris. Often Genera that look a lot like Iris are giving a common name of Iris, for example the following:
Generally Plants in the Iris Family, Iridaceae are refered to as Irids but some species that apear very Iris like have been given common names with Iris in them. Also Some genera such as Pardanthopsis, (Iris dichotoma); Belamcanda, (Iris domestica); and Hermodactylus, (Iris tuberosa) are better known under their former names than their newer Iris names.
-- Main.RPries - 2012-01-14