Nymphaeales is a
botanical name at the rank of
order. When recognized, it includes
water lilies and sometimes other
aquatic plants. This order is not part of the
APG II system's 2003 plant classification (unchanged from the
APG system of 1998), which instead has a broadly circumscribed family
Nymphaeaceae (including
Cabombaceae) unplaced in any order. It is recognized by some
systems of plant taxonomy, but others use different placements for the families in this order. In particular some plant systematists using the APG II system now use this order and circumscribe it to include the
Nymphaeaceae and
Cabombaceae. A 2007 study has found that
Hydatellaceae also belongs to this group.
[1]This order is considered to be a basal, or early diverging, group of angiosperms. The families of this order are united by being families of aquatic herbs and are known from the fossil record as early as the Lower Cretaceous.
The Cronquist system, of 1981, placed it in subclass Magnoliidae, in class Magnoliopsida [=dicotyledons] of division Magnoliophyta [=angiosperms]. It used this circumscription
The Thorne system (1992) placed it in superorder Nymphaeanae in subclass Magnoliideae [=dicotyledons] in class Magnoliopsida [=angiosperms]. It used this circumscription
