Podostemales

(botany) An order of dicotyledonous plants in the subclass Rosidae; plants are submerged aquatics with modified, branching shoots and small, perfect flowers having a superior ovary and united carpels.

An order of flowering plants, division Magnoliophyta (Angiospermae), in the subclass Rosidae of the class Magnoliopsida (dicotyledons). The order consists of only the family Podostemaceae, with about 200 species, the greatest number occurring in tropical America. They are submerged aquatics with modified, branching, often thalluslike shoots, and small, perfect flowers with a much reduced perianth. See also Magnoliopsida; Rosidae.