• Scientific name: Helanthium bolivianum
• Synonym: Echinodorus angustifolius
• Common name: -
• Family: Alismataceae
• Group: Aquarium plants
• Max height: 20-40 cm
• Distribution: South America, Brazil (Mato Grosso region)
• Habitat: Marshes, swamps, shallow ponds
• Substrate: Plain washed gravel
• Placement in aquarium: Middleground
• Planting density: 1 plant for 20 cm²
• Lighting needs: Medium-Bright
• Temperature: 20-28 °C
• pH: 6,5-7,5
• Hardness: 5-12 NK°

Description: A small, amphibious bog plant. Aerial leaves are lanceolate, 10-15 c, long, up to 1 cm wide with almost no petiole. The aquarium plant posses slender, ribbon-shaped leaves that are 20-40 cm long, 0,5-0,8 cm wide, long tipped, narrowing towards the base of the leaf, leaving almost no petiole. Strong light and CO2 certainly contribute to its rapid growth, but are not necessary, making it a good candidate for tanks with lower light and slower growth rates. Without sufficient iron, it often takes on a pale cast. Its long leaves are similar to Vallisneria, making it suitable to provide a green background or side.

Echinodorus angustifolius propagates by runners, and plantlets will develop along these. In time each plantlet will develop its own root system, at this stage they can be separated from the mother plant and re-planted elsewhere in the aquarium.