Cabomba is a genus of perennial, rhizomatous, aquatic herbs in the family Cabombaceae native to tropical and subtropical America. It has divided submerged leaves in the shape of a fan (hence the vernacular name fanwort) and is much favoured by aquarists as an ornamental and oxygenating plant for fish tanks. One species, Cabomba caroliniana, is a nationally declared weed in Australia, where it has choked up waterways after escaping from aquaria.

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