Contortion Vallisneria (Vallisneria asiatica var. biwaensis) is a twisted-leaf Vallisneria from Asia, with a tropical and subtropical range connected to slow-moving freshwater habitats, shallow streams, ponds, and lake edges. It is known for its narrow ribbon-like leaves that curl and twist, giving the plant more movement than standard straight Vallisneria.

This plant grows from a rooted crown and spreads by runners once settled. In aquariums, it works best as a background plant or side-placement plant where the curled leaves can create a soft grassy wall without looking too stiff or formal.

Contortion Vallisneria is a strong choice for low-tech planted aquariums because it does not require CO2 and adapts well to common aquarium conditions. It adds natural cover for fish, shrimp, and fry while giving the back of the aquarium a clean planted look.