Aquatic or semi-aquatic perennial herbs, often rooting from lower nodes. Leaves alternate, pinnatifid to pinnatissect or bipinnatissect. Inflorescence of axillary 1-several-flowered cymes in upper axils. Flowers bisexual, each subtended by a pair small bracteoles; pedicels short; sepals 2, triangular; petals 2, slightly hooded, keeled; stamens 4; anthers oblong, 4-celled, non-apiculate, filaments short. Ovary 2-celled, slightly compressed, smooth to slightly rugose or tuberculate; ovules 2; styles 2; stigmas fimbriate. Fruit an indehiscent 2-celled nut, slightly compressed to 2-winged.
An endemic Australian genus of 2 species.
Often treated as part of Haloragis but first recognised as a genus in 1814. A phylogenetic analysis by Moody & Les (2007) using molecular and morphological markers, showed Meionectes to be quite distinct from the Haloragis-Gonocarpus clade.
Moody, M.L.; Les, D.H. (2007). Phylogenetic systematics and character evolution in the angriosperm family Haloragaceae. *American Journal of Botany * 94(12): 2005–2025.
