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.
Description
Vegetative characteristics Cabomba are perennial, rhizomatous, aquaticPellegrini, M. O. O. & Jardim Botânico do Rio de Janeiro. (n.d.). Cabomba Aubl. Flora E Funga Do Brasil. Retrieved 5 February 2025, from https://floradobrasil.jbrj.gov.br/FB6610 herbsCabomba Aublet - Database of Vascular Plants of Canada (VASCAN). (n.d.). https://data.canadensys.net/vascan/taxon/924 with short, brown rhizomes. The roots, which are formed on the lower nodes of the stems,T.D. Stanley & A.E. Orchard. Cabomba, in P.G. Kodela (ed.), Flora of Australia. Australian Biological Resources Study, Department of Climate Change, Energy, the Environment and Water: Canberra. https://profiles.ala.org.au/opus/foa/profile/Cabomba [Date Accessed: 6 February 2025] are delicate, brown to white, and branched. The long, cylindrical, flexible,Manaaki Whenua – Landcare Research. (n.d.). Cabomba Aubl. Flora of New Zealand. Retrieved 5 February 2025, from https://www.nzflora.info/factsheet/taxon/Cabomba.html delicate, branched or unbranched stems are 2–4 mm wide,Ørgaard, M. (1991). The genus Cabomba (Cabombaceae)–a taxonomic study. Nordic Journal of Botany, 11(2), 179-203. and up to 4 m long. Both floating and submerged leaves are present, but only few floating leaves are produced,Royal Botanic Gardens Victoria. (n.d.). Cabomba. VicFlora Flora of Victoria. Retrieved 5 February 2025, from https://vicflora.rbg.vic.gov.au/flora/taxon/14a740cd-b533-4c51-a0e4-0175fcc33499 and they may be absent entirely.Fassett, N. C. (1953). A Monograph of Cabomba. Castanea, 18(4), 116–128. http://www.jstor.org/stable/4031558 The submerged leaves are divided into 3–7 dichotomously or trichotomously branched parts.Cabomba in Flora of North America @ efloras.org. (n.d.). Retrieved 5 February 2025, from http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=104954 The floating leaves are inconspicuous.Cabomba in Flora of China @ efloras.org. (n.d.). Retrieved 5 February 2025, from http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=104954 Generative characteristics The solitary, hermaphrodite, pedicellate, chasmogamous, scentless, actinomorphic, white, yellow, or purple, trimerous or rarely di- and tetramerous flowers extend beyond the water surface. The petals are oval-shaped, and are usually about across when fully developed. The petals are unlike the sepals in that the former have two yellow ear-shaped nectaries at the base. Petals may also have purplish edges. Flowers are protogynous, having primarily female sexual structures on the first day of appearance and then switching to male on the second and subsequent days. Pollination occurs above the waterline. Principal pollinators are flies and other small flying insects.
Cytology Various chromosome counts have been observed in Cabomba: 2n = 26, 39, 52, 78, 104.
Taxonomy It was published by Jean Baptiste Christophore Fusée Aublet in 1775. The type species is Cabomba aquatica Aubl. Species The genus Cabomba Aubl. consists of six extant species: Cabomba aquatica Aubl. (fanwort) Cabomba caroliniana A. Gray (green cabomba) Cabomba furcata Schult. & Schult.f. (red cabomba) Cabomba haynesii Cabomba palaeformis Fassett Cabomba schwartzii Rataj
And four fossil species: Cabomba gracilis Cabomba gracilis Newb. (n.d.). The International Fossil Plant Names Index (IFPNI). Retrieved 18 February 2025, from https://ifpni.org/species.htm?id=F77FCE1B-5F22-4EA3-A22E-BE7DED077EBF Cabomba grandis Cabomba grandis Newb. (n.d.). The International Fossil Plant Names Index (IFPNI). Retrieved 18 February 2025, from https://ifpni.org/species.htm?id=63C5D164-498E-4160-B964-A5A2295D89AB Cabomba inermis Cabomba inermis (Newb.) Hollick in Newb. (n.d.). The International Fossil Plant Names Index (IFPNI). Retrieved 18 February 2025, from https://ifpni.org/species.htm?id=E756C876-9AA1-44E0-BC16-97E187BFCABA Cabomba pitonii Cabomba pitonii L. Laurent, Marty in L. Piton. (n.d.). The International Fossil Plant Names Index (IFPNI). Retrieved 18 February 2025, from https://ifpni.org/species.htm?id=30D7B8D6-3F0D-C3C7-9E11-A5448E2A3995 Putative hybridisation It has been speculated, that Cabomba haynesii may be a result of a hybridisation event involving Cabomba palaeformis and Cabomba furcata. Etymology The generic name Cabomba may be derived from an aboriginal name of the plant in Guyana.
Distribution It is native to tropical and subtropical America, and the centre of diversity is Brazil.
Ecology Pollination The flowers are pollinated by flies and bees.Matias, L. Q., & Nascimento, H. P. D. (2021). Flora of Ceará, Brazil: Cabombaceae. Rodriguésia, 72, e00592019. Habitat Cabomba occurs in ponds, floodplains, swamps, and creeks.
Cabomba as an aquarium plant Cabomba species are popular aquarium plants. Cabomba caroliniana is easily cultivated and is tolerant of various substrates and temperatures. However, in dimly lit conditions the leaves grow small and the internodes of the stems elongate. By contrast, Cabomba furcata is considered to be difficult to cultivate in the aquarium, as it requires soft, acid water and a high light intensity.
Invasive species Use in the aquarium trade has led to some species being introduced to other parts of the world, such as Australia, where Cabomba caroliniana it is a nationally declared weed. Having arrived in 1967, it spread rapidly in waterways and out-competed native plants, threatening water supplies, especially along the eastern side of the continent. In Australia, Cabomba caroliniana has been targeted by both chemical,Day, C., Petroeschevsky, A., Pellow, B., Bevan, J., O’Dwyer, T., St Lawrence, A., & Smith, G. (2014). Managing a priority outlier infestation of Cabomba caroliniana in a natural wetland in the Blue Mountains, NSW, Australia–could this be eradication. In Draft paper to 19th Australasian Weeds Conference, Hobart, Australia. and biological control. Herbicide treatment is effective, yet also damages the remaining aquatic flora and fauna. The cabomba weevil (Hydrotimetes natans) is introduced to waterways as a means of biological control of Cabomba caroliniana.Australian Government Department of Agriculture, Fisheries and Forestry. (2023, 9 May). Hydrotimetes natans for the biological control of Cabomba caroliniana. Retrieved 2 October 2023, from https://www.agriculture.gov.au/biosecurity-trade/policy/risk-analysis/biological-control-agents/risk-analyses/completed-risk-analyses/ra-release-hydrotimetes-natans They consume the plant's tips and inflict significant harm when present in large quantities. Larvae burrow within the stems and result in substantial damage to the main stem due to tissue necrosis.Kumaran, N., Vance, T. J., Comben, D., Dell, Q., Oleiro, M. I., Goñalons, C. M., ... & Raghu, S. (2022). "Hydrotimetes natans as a suitable biological control agent for the invasive weed Cabomba caroliniana." Biological Control, 169, 104894.
Likewise, Cabomba furcata has become an invasive species in Kerala, India, in the Kalutara district of Sri Lanka,Yakandawala, D. M. D., Yakandawala, K., Madola, I., & Herath, H. M. L. K. (2022). Would history repeat? Detection of Cabomba furcata, a potential invasive plant in natural ecosystems of Sri Lanka. Ceylon Journal of Science, 51(2), 155-163. in Chini Lake, Malaysia,Yunoh, S. M. M. (2011, 28 December). Cabomba furcata (Cabombaceae). Malaysia Biodiversity Information System (MyBIS). https://www.mybis.gov.my/art/130 and Taiwan.Wu, S. H., Yang, T. A., Teng, Y. C., Chang, C. Y., Yang, K. C., & Hsieh, C. F. (2010). Insights of the latest naturalized flora of Taiwan: change in the past eight years. Taiwania, 55(2), 139-159. Its presence leads to a decline of water quality and biodiversity.Rao, G. P., & Rani, K. S. A report on the biological invasion of alien plant species red Cabomba in the Kozhikode district of Kerala state and its impact on agro-ecosystem. Issues in Biodiversity Conservation and Management, 103.
References
External links
InvadingSpecies.com United States Department of Agriculture, Germplasm Resources Information Network (GRIN): Cabomba Information about Cabomba for Aquarium Hobbyists