Nuphar lutea

Perennial aquatic herb with both floating and submerged leaves.

The lamina of floating leaves is 15–30 cm long. The length of the petiole of floating leaves can even exceed 2 m.

The rhizome is a 3–7 cm thick, robust, horizontal rhizome growing at the bottom of a body of water.

The leaves are petiolate and exstipulate. There are hollow air chambers of equal size inside the petioles. The submerged leaves are rather short-petiolate and the lamina is rounded, thin and rugose. The floating leaves are long-petiolate and the petiole is obtusely triangular. The lamina of floating leaves is oval, with a deep sinus at the base, entire, waxy-lustrous, glabrous and light green on both sides of the lamina. The veins of the lamina are seemingly dichotomous and end at the margin of the lamina.

The flower is actinomorphic, 4–6 cm wide, gibbous and fragrant. The calyx is typically five-leaved. The outer sepals are green on the dorsal side. The inner sepals are yellow on both sides. The corolla consists of 15–20 petals, which are shorter than the sepals and entirely yellow. The androecium and gynoecium are multiple-leaved. The ovary of the pistil is superior and with multiple locules.

The fruit is a green or brownish capsule. The capsule matures above water. A seed is 4–5 mm long.