"Azolla caroliniana" is a commonly used name for a species which is presented as Azolla cristata in this database.
Recent examinations have shown that the plant originally described as A. caroliniana (the typus of A. caroliniana) does not belong to A. cristata but to Azolla filiculoides .
Thus, the name Azolla caroliniana can be considered a synonym of the older name A. filiculoides, and was only erroneously used for A. cristata.
