Alismatidae

Alismatidae is a botanical name at the rank of subclass. of the subclass will vary with the being used (there are many such systems); the only requirement being that it includes the family Alismataceae. It is a relatively new name: earlier systems, such as the Engler and Wettstein systems, used the name Helobiae for a comparable unit.

The Takhtajan system treats this as one of six subclasses within the class Liliopsida (=monocotyledons). It consists of:

The Cronquist system treats this as one of four subclasses within the class Liliopsida (=monocotyledons). It consists of (1981):

This subclass comprises less than five hundred species total: many of these are aquatic or plants (see Alismatidae info).

The APG II system does not use formal botanical names above the rank of order; it assigns most of the plants involved to the (expanded) order Alismatales, in the clade 'monocots', although the plants in Cronquist's order Triuridales are assigned to quite different placements.

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