Echinodorus grisebachii 'Amazonicus'

Echinodorus grisebachii 'Amazonicus', the narrow-leaved Amazon sword, is widely known as E. amazonicus. It belongs to the species Echinodorus grisebachii, widely spread in the American tropics and known for its many varieties. E. grisebachii 'Bleherae' and E. grisebachii 'Parviflorus' are also counted amongst this species.
First, this plant was brought onto the market in 1938, back then still under the erronous name "E. brevipedicellatus" (a synonym of Echinodorus longipetalus). It was long carried under that name. Only in 1970, Karel Rataj described it as a new species (E. amazonicus). Its origins are reported to lie in the Brazilian Amazon depression (Rondônia and Pará), where it was found growing submersed in 50 to 100 cm deep stagnant to slow-flowing water.

Usually, forms of E. grisebachii that are quite similar to E. grisebachii 'Parviflorus' and 'Bleherae' are brought into trade under the name E. amazonicus. Those plants grow to a height of around 40 cm when cultivated submersed. The original type of E. grisebachii 'Amazonicus' was current in aquaristics decades ago and differs significantly from those. When cultivated submersed, it developes very narrow, lanceolate leaf blades curving sidewards like a sickle. In the aquarium, it can grow to over 60 cm in height, like E. grisebachii 'Bleherae', but differs from the latter mainly in its narrower leaf form.
Well-growing submersed plants sprout 1 to 2 new leaves per week and often develop long flower stalks with adventitious plants floating below the waterline.

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