Hydatellales is a small order of monocotflowering plants, including one family, the Hydatellaceae. Newer classification systems, including the Angiosperm Phylogeny Group's APG II system, include the Hydatellaceae in order Poales.
A subclass of the class Liliopsida (monocotyledons) of the division Magnoliophyta (Angiospermae), the flowering plants, consisting of 7 orders, 16 families, and nearly 15,000 species.
The orders include Commelinales, Eriocaulales, Restionales, Juncales, Cyperales, Hydatellales, and Typhales.
For further information see separate articles on each order.