Retrospiralis

Cryptocoryne retrospiralis is one of the taller water trumpets, a grass-like species from India that pushes its narrow, ribbon-shaped leaves to about 40 cm in the aquarium. It grows mostly in the southwestern part of the country, with scattered records to the southeast and northeast, usually in slow streams and on swampy ground. The name points to the twisted spathe, the showy part of the flower.

Flowgrow publishes water-chemistry ranges for it but no difficulty or growth rating, so the temperature and pH here come from its slider while the other two figures are editorial. It accepts temperatures of 20 to 26 °C and a pH of 5 to 8, and it does not demand bright light or CO₂, behaving like a robust background crypt that spreads by runners. Commercial availability is limited and most plants change hands between hobbyists.

It is close to Cryptocoryne crispatula, and plants sold under either name sometimes resemble each other closely enough to confuse buyers.