This genus markedly differs from Echinodorus by a typical paniculate inflorescence shaped as a regular pyramid. Flowering stalk is 40 – 50 cm tall, inflorescence up to 12 – 20 cm long, flowers arranged in 2 - 6 whorls, bracts of the lower whorl reach a length of 2.5 – 4 cm and a width of 0.5 - 0.8 cm, bracts in further whorls being only 2 – 5 mm long. Corolla white, stamens usually 9. Compound fruit comprises maximum 20 achenes, each 1.4 - 1.6 mm long x 1 mmwide with a broad crested keel and with crested ribs and 1 or 2 long glands on each face, beak 0.2 mm long.