1502 Nymphaea L.
- L., Sp. Pl.: 510 (1753) nom. cons..
Notes: All the northern taxa belong to a Nymphaea alba aggregate. Nymphaea tetragona s. lat. is the most distinctive of the northern taxa. There are arguments both for a wide, collective concept of N. alba L. and for keeping the nearly circumboreal N. tetragona s. lat. apart from the rest of the aggregate. We follow the latter course. Morphological (Volkova and Shipunov 2008) and molecular studies (Volkova et al. 2010) show that one major part of N. alba s. lat. - N. candida C. Presl & J. Presl (N. alba subsp. candida (C. Presl & J. Presl) Korsh.) - is a fertile hybrid species from N. alba s. str. and N. tetragona s. str., reaching far outside the range of the latter parent.
The two parts of N. tetragona s. lat. have been treated as two species or two subspecies. Wiersema (1997) accepted N. leibergii as species and we follow that course.