About Nuphar sagittifolia (Walter) Pursh
Nuphar sagittifolia (Walter) Pursh is a perennial, rhizomatous, aquatic, heterophyllous herb. Its rhizomes measure 2–2.5 cm wide. The species produces both floating and submerged leaves, though submerged leaves are more common. Submerged leaves are crisped, membranous, and larger than floating leaves. Floating leaves are glabrous, green, and linear to lanceolate in shape; they grow 15–30(–50) cm long and 5–10(–11.5) cm wide. Leaf petioles are subterete and 1.5–7 mm wide. Flowers are yellow and 2–3 cm wide, borne on glabrous peduncles 3–8 mm wide. Each flower has 6 sepals and thick, oblong yellow petals. The gynoecium is made up of 11–15 carpels. The green stigmatic disk is 14–18 mm wide, almost entire, and marked with 11–15 stigmatic rays. Fruits are ovoid and green, measuring 3–3.5 cm long and 2–3 cm wide. Fruits contain seeds that are 4–5 mm long and 3 mm wide. This species flowers and fruits from April to October. It is an aquatic plant that grows in acidic water up to 2.1 m deep, found in lakes, ponds, and slow-moving rivers of coastal plains.
