Rataj places it in his Section Macrophylli - Subgenus Echinodorus

Description

Petioles 2 - 3 x longer than the blade, membraneously alate on the base, thin to densely pilose under the blade. Pubescence simple or stellate and absent on young or submerged plants. Blade membraneous, sagittato-cordate or triangularly obovate with long blunt lobes, approximately as wide as the midrib length and widest at the base. Blade (6.5) - 20 - 30 cm long and (7_ - 20 - 30 cm wide with 11 - 13 veins (7 - 15 are possible). No pellucid markings.

Stem upright, about twice as long as the leaves, cylindrical, between the whorls triangular, pubescent under whorls as well as petioles.

Inflorescence

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. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...

 rarely racemose, usually paniculate having 6 - 13 whorls containing 6 - 9 flowers each. Bracts lanceolate, densely ribbed. Bracts in the first whorl as long as the pedicels, in the other whorls they are a third shorter. Pedicels 1 - 3.5 cm long, sepals broadly ovate, leather-like, densely ribbed, 5 - 6 mm long, petals white, obovate, 15 - 18 mm long, stamens 20 - 24, filaments longer than the anthers, pistils numerous, style longer than the ovary.

Aggregate fruit

Fruit

In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...

 globular, echinate, 6 - 8 mm in diameter. Achenes flat, subovately-cuneate, 3 x 1.5 mm with 3 - 5 (usually 3) lateral ribs and 2 - 3 oblong and further 3 - 5 small round glands. Stylar beak usually straight, approximately 0.75 mm.

Cultivation

Grow at tropical temperatures with plenty of light and a rich substrate. It can stand lower temperatures however if acclimatised, though it will stay rather smaller and grow more slowly. Water conditions don't seem to be critical. In the smaller aquarium it will often quickly form emerse leaves, which prefer moist conditions and don't like being dried out by being too near lamps etc. It is easy to grow and makes a very good specimen plant for the larger aquarium

Aquarium

An aquarium is a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, marine mammals, turtles, and aquatic plants...

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Distribution

Guyana

Guyana

Guyana , officially the Co-operative Republic of Guyana, previously the colony of British Guiana, is a sovereign state on the northern coast of South America that is culturally part of the Anglophone Caribbean. Guyana was a former colony of the Dutch and of the British...

 to Brazil

Brazil

Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...

 and Argentina

Argentina

Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

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See also: List of plants of Cerrado vegetation of Brazil