A genus of 20-50 species, annual and perennial herbs of aquatic, wetland, and upland habitats, nearly cosmopolitan. This genus should be included in a greatly expanded Plantaginaceae.
Ref: APG IV (2016); Crow & Hellquist (2000a); Erbar & Leins In Kadereit (2004); Fassett (1951); Lansdown (2009); Lansdown (2019) In Flora of North America Editorial Committee (2019); Prančl et al. (2020). Show full citations.