''Echinodorus'', commonly known as burhead or Amazon sword, is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

of plants in the family Alismataceae, native to the

Western Hemisphere The Western Hemisphere is the half of the planet Earth that lies west of the prime meridian (which crosses Greenwich, London, United Kingdom) and east of the antimeridian. The other half is called the Eastern Hemisphere. Politically, the term We ...

from the central United States to Argentina. Its

scientific name In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

is derived from

Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic peri ...

' – "rough husk" - and ' – "leathern bottle" - alluding to ovaries, which in some species are armed with persistent styles, forming prickly head of fruit. Some of the species are commonly cultivated in artificial aquatic habitats.

Description

The plants are annual or

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 ...

, growing emersed, floating-leaved, or seasonally submersed, leaves glabrous to stellate-pubescent;

rhizomes In botany and dendrology, a rhizome (; , ) is a modified subterranean plant stem that sends out roots and shoots from its nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from axillary buds and grow hori ...

present or absent;

stolons In biology, stolons (from Latin '' stolō'', genitive ''stolōnis'' – "branch"), also known as runners, are horizontal connections between organisms. They may be part of the organism, or of its skeleton; typically, animal stolons are external s ...

absent;

corm A corm, bulbo-tuber, or bulbotuber is a short, vertical, swollen underground plant stem that serves as a storage organ that some plants use to survive winter or other adverse conditions such as summer drought and heat (perennation). The word ' ...

s absent; tubers absent.

Root In vascular plants, the roots are the organs of a plant that are modified to provide anchorage for the plant and take in water and nutrients into the plant body, which allows plants to grow taller and faster. They are most often below the sur ...

s not septate. Leaves

sessile Sessility, or sessile, may refer to: * Sessility (motility), organisms which are not able to move about * Sessility (botany), flowers or leaves that grow directly from the stem or peduncle of a plant * Sessility (medicine), tumors and polyps that ...

petiolate Petiole may refer to: *Petiole (botany), the stalk of a leaf, attaching the blade to the stem *Petiole (insect anatomy) In entomology, petiole is the technical term for the narrow waist of some hymenopteran insects, especially ants, bees, a ...

; petioles triangular, rarely terete; blade with translucent markings as dots or lines present or absent, linear to lanceolate to ovate, base attenuate to cordate, margins entire or undulating, apex obtuse to acute.

Inflorescences An inflorescence is a group or cluster of flowers arranged on a Plant stem, stem that is composed of a main branch or a complicated arrangement of branches. Morphology (biology), Morphologically, it is the modified part of the shoot of sperma ...

racemes A raceme ( or ) or racemoid is an unbranched, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are produced as the s ...

panicles A panicle is a much-branched inflorescence. (softcover ). Some authors distinguish it from a compound spike inflorescence, by requiring that the flowers (and fruit) be pedicellate (having a single stem per flower). The branches of a panicle are o ...

, rarely umbels, of 1–18 whorls, erect or decumbent, emersed;

bracts In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves. They may be smaller, larger, or of ...

coarse, apex obtuse to acute, surfaces smooth or papillose along veins, apex obtuse to acute.

Flowers 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 ...

bisexual, subsessile to pedicellate;

subtending pedicels, subulate to lanceolate, shorter than to longer than pedicels, apex obtuse to acute; pedicels ascending to recurved; receptacle convex;

sepals A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 The term ''sepalum'' was coined b ...

recurved to spreading,

herbaceous Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials. Definitions of "herb" and "herbaceous" The fourth edition of t ...

to leathery, sculpturing absent; petals white, entire; stamens 9–25; filaments linear, glabrous; pistils 15–250 or more, spirally arranged on convex receptacle, forming head, distinct;

ovules In seed plants, the ovule is the structure that gives rise to and contains the female reproductive cells. It consists of three parts: the ''integument'', forming its outer layer, the ''nucellus'' (or remnant of the megasporangium), and the fe ...

1; style terminal or lateral.

Fruits In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering. Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particula ...

plump, often longitudinally ribbed, sometimes flattened, rarely abaxially keeled, abaxial wings absent, lateral wings absent, glands often present.

Cultivation

''Echinodorus'' are by nature marsh and bog plants that can grow submersed. Many species are grown in

aquariums An aquarium (plural: ''aquariums'' or ''aquaria'') is a vivarium of any size having at least one transparent side in which aquatic plants or animals are kept and displayed. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, a ...

. They prefer good light and grow best in a deep, nutrient-rich substrate. Most will grow in variable water conditions, though the majority need tropical or sub-tropical temperature ranges. Propagation is by division or by adventitious new plants developing on submerged flowering stems. The larger species make magnificent specimen plants for the larger aquarium, though they may form aerial leaves in good conditions. If the

inflorescence An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...

forms submersed, small plantlets will form instead of flowers. If grown emersed and kept humid, flowers and seeds will normally readily form. The seeds can be grown in damp sand in warm, damp conditions. Additional CO₂ often helps in strong growth. Many species are popular in the

aquarium An aquarium (plural: ''aquariums'' or ''aquaria'') is a vivarium of any size having at least one transparent side in which aquatic plants or animals are kept and displayed. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, aq ...

pond A pond is an area filled with water, either natural or artificial, that is smaller than a lake. Defining them to be less than in area, less than deep, and with less than 30% emergent vegetation helps in distinguishing their ecology from th ...

. The Amazon sword plants are one of the most popular

plants for their attractive form and general hardiness. A submerged culture system was developed for rapid micropropagation of this commercially important aquarium plant, ‘Amazon sword’ (''Echinodorus'' ‘Indian Red’).

Taxonomy

The genus ''Baldellia'' seems to be very closely related. In the latest revision by

Karel Rataj Karel may refer to: People * Karel (given name) * Karel (surname) * Charles Karel Bouley, talk radio personality known on air as Karel * Christiaan Karel Appel, Dutch painter Business * Karel Electronics, a Turkish electronics manufacturer * Gr ...

, 62 species, 2 subspecies, and 2 varieties are listed. All

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of Echinodorus are variable according to hether they are growing emerse or submerged and their growing conditions. In addition they can hybridise in the wild or through artificial means. Many forms have been given subspecific status or as named forms in the

trade. Accoording to aquarists some of these forms persist in all growing conditions.

Species

As of May 2014, 30 species are accepted by authorities at Kew Royal Botanic Gardens:Kew World Checklist of Selected Plant Families
/ref> Included in the list below are names accepted in previous versions but now regarded as synonyms. Echinodorus grisebachii (5)-flower view

#'' Echinodorus angustifolius'' Rataj - syn of ''

Helanthium bolivianum ''Helanthium bolivianum'' is a species of plant in the Alismataceae. It is native to southern Mexico, Central America, the West Indies and South America.Lehtonen, Samuli & Myllys, Leena. 2008. Cladistics 24(2): 228 References External linksp ...

'' (Rusby) Lehtonen & Myllys #'' Echinodorus argentinensis'' Rataj - syn of '' Echinodorus grandiflorus'' (Cham. & Schltdl.) Micheli #''

Echinodorus aschersonianus ''Echinodorus uruguayensis'' or ''Echinodorus osiris'' is a plant species in the Alismataceae. It is native to South America (Brazil, Argentina, Paraguay, Uruguay, Chile). Description Submersed leaves (5)-30-50 cm long, blades ribbon-shaped ...

'' Graebn. - syn of '' Echinodorus uruguayensis'' Arechav #'' Echinodorus berteroi'' (Spreng.) Fassett - from

South Dakota South Dakota (; Sioux language, Sioux: , ) is a U.S. state in the West North Central states, North Central region of the United States. It is also part of the Great Plains. South Dakota is named after the Lakota people, Lakota and Dakota peo ...

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...

#''

Echinodorus bleherae ''Echinodorus grisebachii'' or ''Echinodorus amazonicus'' is commonly known as Amazon sword plant, although other plants are also known under this common name. The aquatic plant is cultivated for and used in ponds and artificial aquatic habitats. ...

'' or '' E. bleheri'' Rataj - syn of ''

Echinodorus grisebachii ''Echinodorus grisebachii'' or ''Echinodorus amazonicus'' is commonly known as Amazon sword plant, although other plants are also known under this common name. The aquatic plant is cultivated for and used in ponds and artificial aquatic habitats. ...

'' Small #'' Echinodorus bracteatus'' Micheli - from

Nicaragua Nicaragua (; ), officially the Republic of Nicaragua (), is the largest country in Central America, bordered by Honduras to the north, the Caribbean to the east, Costa Rica to the south, and the Pacific Ocean to the west. Managua is the cou ...

Ecuador Ecuador ( ; ; Quechua: ''Ikwayur''; Shuar: ''Ecuador'' or ''Ekuatur''), officially the Republic of Ecuador ( es, República del Ecuador, which literally translates as "Republic of the Equator"; Quechua: ''Ikwadur Ripuwlika''; Shuar: ''Eku ...

#'' Echinodorus cordifolius'' (L.) Griseb. - from

Illinois Illinois ( ) is a U.S. state, state in the Midwestern United States, Midwestern United States. Its largest metropolitan areas include the Chicago metropolitan area, and the Metro East section, of Greater St. Louis. Other smaller metropolita ...

Paraguay Paraguay (; ), officially the Republic of Paraguay ( es, República del Paraguay, links=no; gn, Tavakuairetã Paraguái, links=si), is a landlocked country in South America. It is bordered by Argentina to the south and southwest, Brazil to th ...

#'' Echinodorus cylindricus'' Rataj -

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

#'' Echinodorus decumbens'' Kasselm. -

#'' Echinodorus densinervis'' Somogyi -

#'' Echinodorus eglandulosus'' Rataj -

#''

Echinodorus emersus ''Echinodorus emersus'' is a species of plant in the family Alismataceae from South America. References Further reading *Lehtonen, Samuli. "Systematics of the Alismataceae—A morphological evaluation." Aquatic Botany 91.4 (2009): 279–290. * ...

'' Lehtonen -

Peru , image_flag = Flag of Peru.svg , image_coat = Escudo nacional del Perú.svg , other_symbol = Great Seal of the State , other_symbol_type = Seal (emblem), National seal , national_motto = "Fi ...

Bolivia , image_flag = Bandera de Bolivia (Estado).svg , flag_alt = Horizontal tricolor (red, yellow, and green from top to bottom) with the coat of arms of Bolivia in the center , flag_alt2 = 7 × 7 square p ...

#'' Echinodorus floribundus'' (Seub.) Seub. -

Veracruz Veracruz (), formally Veracruz de Ignacio de la Llave (), officially the Free and Sovereign State of Veracruz de Ignacio de la Llave ( es, Estado Libre y Soberano de Veracruz de Ignacio de la Llave), is one of the 31 states which, along with Me ...

#'' Echinodorus gabrielii'' Rataj -

#'' Echinodorus glaucus'' Rataj -

#'' Echinodorus grandiflorus'' (Cham. & Schltdl.) Micheli -

Uruguay Uruguay (; ), officially the Oriental Republic of Uruguay ( es, República Oriental del Uruguay), is a country in South America. It shares borders with Argentina to its west and southwest and Brazil to its north and northeast; while bordering ...

Venezuela Venezuela (; ), officially the Bolivarian Republic of Venezuela ( es, link=no, República Bolivariana de Venezuela), is a country on the northern coast of South America, consisting of a continental landmass and many islands and islets in th ...

Florida Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and to ...

#''

'' Small - from

#'' Echinodorus heikobleheri'' Rataj -

#'' Echinodorus horizontalis'' Rataj - from

Guyana Guyana ( or ), officially the Cooperative Republic of Guyana, is a country on the northern mainland of South America. Guyana is an indigenous word which means "Land of Many Waters". The capital city is Georgetown. Guyana is bordered by the ...

#'' Echinodorus inpai'' Rataj -

#'' Echinodorus isthmicus'' Fassett - syn of ''

'' (Rusby) Lehtonen & Myllys #'' Echinodorus lanceolatus'' Rataj -

#'' Echinodorus longipetalus'' Micheli - from

Suriname Suriname (; srn, Sranankondre or ), officially the Republic of Suriname ( nl, Republiek Suriname , srn, Ripolik fu Sranan), is a country on the northeastern Atlantic coast of South America. It is bordered by the Atlantic Ocean to the north ...

#'' Echinodorus longiscapus'' Arechav. -

#'' Echinodorus macrocarpus'' Rataj - syn of '' Echinodorus pubescens'' (Mart. ex Schult.f.) Seub. ex Warm. -

#'' Echinodorus macrophyllus'' (Kunth) Micheli -

#'' Echinodorus major'' (Micheli) Rataj -

#'' Echinodorus nymphaeifolius'' (Griseb.) Buchenau - syn of '' Albidella nymphaeifolia'' (Griseb.) Pichon #'' Echinodorus opacus'' Rataj - syn of '' Echinodorus uruguayensis'' Arechav #''

Echinodorus osiris ''Echinodorus'', commonly known as burhead or Amazon sword, is a genus of plants in the family Alismataceae, native to the Western Hemisphere from the central United States to Argentina. Its scientific name is derived from Ancient Greek ' – "r ...

'' Rataj - syn of '' Echinodorus uruguayensis'' Arechav #'' Echinodorus ovalis'' C.Wright - syn of '' Echinodorus cordifolius'' (L.) Griseb #'' Echinodorus palaefolius'' (Nees & Mart.) J.F.Macbr. - Nayarit,

Minas Gerais Minas Gerais () is a state in Southeastern Brazil. It ranks as the second most populous, the third by gross domestic product (GDP), and the fourth largest by area in the country. The state's capital and largest city, Belo Horizonte (literally ...

#'' Echinodorus paniculatus'' Micheli in A.L.P.de Candolle & A.C.P.de Candolle - from

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

#'' Echinodorus reptilis'' Lehtonen -

#'' Echinodorus scaber'' Rataj - from

#'' Echinodorus subalatus'' (Mart. ex Schult.f.) Griseb. - from

; also

Cuba Cuba ( , ), officially the Republic of Cuba ( es, República de Cuba, links=no ), is an island country comprising the island of Cuba, as well as Isla de la Juventud and several minor archipelagos. Cuba is located where the northern Caribbea ...

#''

Echinodorus tenellus ''Helanthium tenellum'', the pygmy chain sword, is a species of plants in the Alismataceae. It is native to the eastern United States (from Texas to Florida, north to Michigan and Massachusetts), southern Mexico (Chiapas, Veracruz), West Indies ( ...

'' (Mart. ex Schult.f.) Buchenau - syn of '' Helanthium tenellum'' (Mart. ex Schult.f.) J.G.Sm. in N.L.Britton #'' Echinodorus trialatus'' Fassett -

Panama Panama ( , ; es, link=no, Panamá ), officially the Republic of Panama ( es, República de Panamá), is a transcontinental country spanning the southern part of North America and the northern part of South America. It is bordered by Cos ...

Colombia Colombia (, ; ), officially the Republic of Colombia, is a country in South America with insular regions in North America—near Nicaragua's Caribbean coast—as well as in the Pacific Ocean. The Colombian mainland is bordered by the Car ...

#'' Echinodorus tunicatus'' Small - from

Costa Rica Costa Rica (, ; ; literally "Rich Coast"), officially the Republic of Costa Rica ( es, República de Costa Rica), is a country in the Central American region of North America, bordered by Nicaragua to the north, the Caribbean Sea to the no ...

#'' Echinodorus uruguayensis'' Arechav. -

Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the east a ...

#'' Echinodorus virgatus'' (Hook. & Arn.) Micheli - syn of '' Echinodorus palifolius'' (Nees & Mart.) J.F.Macbr

References

External links

''Echinodorus''

Shutting down the chaos engine — or, identifying some problematic Echinodorus (Alismataceae) types

Bibliography

* Lehtonen S and Myllys L. 2008. Cladistic analysis of Echinodorus (Alismataceae): simultaneous analysis of molecular and morphological data. Cladistics 24: 218–239. {{Taxonbar, from=Q596454 Alismataceae genera Aquatic plants