''Eichhornia'', commonly called water hyacinths, was a

polyphyletic A polyphyletic group is an assemblage of organisms or other evolving elements that is of mixed evolutionary origin. The term is often applied to groups that share similar features known as homoplasies, which are explained as a result of converg ...

genus of the aquatic

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...

s family

Pontederiaceae Pontederiaceae is a family of flowering plants. The APG IV system of 2016 (unchanged from the APG III system of 2009, the APG II system of 2003 and the APG system of 1998) places the family in the order Commelinales, in the commelinid clade, ...

. Since it was consistently recovered in three independent lineages, it has been sunk into ''

Pontederia ''Pontederia'' is a genus of tristylous aquatic plants, members of which are commonly known as pickerel weeds. ''Pontederia'' is endemic to the Americas, distributed from Canada to Argentina, where it is found in shallow water or on mud. The genu ...

'', together with '' Monochoria''. Each of the three lineages is currently recognized as subgenera in ''Pontederia'': * ''Pontederia'' subg. ''Cabanisia'', which includes '' P. meyeri'', '' P. paniculata'' (the Brazilian water hyacinth), and '' P. paradoxa'' * ''Pontederia'' subg. ''Oshunae'', which includes the common water hyacinth, '' P. crassipes'' * ''Pontederia'' subg. ''Eichhornia'', which includes '' P. azurea'', '' P. diversifolia'', '' P. heterosperma'', and '' P. natans'' ''Pontederia'' subg. ''Eichhornia'' is pantropical, centered in

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...

but with '' P. natans'' being endemic to continental

Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...

and

Madagascar Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa ...

. The other three species are restricted to the

Neotropics The Neotropical realm is one of the eight biogeographic realms constituting Earth's land surface. Physically, it includes the tropics, tropical Ecoregion#Terrestrial, terrestrial ecoregions of the Americas and the entire South American temperat ...

. It was named in honour of , an early-19th-century

Prussia Prussia, , Old Prussian: ''Prūsa'' or ''Prūsija'' was a German state on the southeast coast of the Baltic Sea. It formed the German Empire under Prussian rule when it united the German states in 1871. It was ''de facto'' dissolved by an em ...

n minister of education.

Description

Its species are

perennial A perennial plant or simply perennial is a plant that lives more than two years. The term ('' per-'' + '' -ennial'', "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also wide ...

aquatic plant Aquatic plants are plants that have adapted to living in aquatic environments (saltwater or freshwater). They are also referred to as hydrophytes or macrophytes to distinguish them from algae and other microphytes. A macrophyte is a plant that ...

s (or hydrophytes) with prostrate and densely branched stems. The inflorescences can have one to 30 conspicuously attractive

flower A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechani ...

s, mostly lavender to pink in colour, rarely white.

References

External links

* {{Taxonbar, from=Q2144596 Freshwater plants Pontederiaceae Commelinales genera Historically recognized angiosperm genera