A family of aquatic or marsh herbs that have either whorled, much-divided leaves (e.g. Myriophyllum and Haloragis), or enormous, radical, rhubarb-like leaves (e.g. Gunnera). The flowers are inconspicuous and solitary, in axils of spikes or dichasia, with no or 2 or 4 tiny sepals and petals and short stamens. The ovary is inferior and wind-pollinated. There are about 120 species, in 10 genera. Distribution is cosmopolitan, but mainly in the southern hemisphere.
Subjects: Plant Sciences and Forestry.