A distinctive aquatic plant, the spotted pondweed (Potamogeton pulcher) is, as its common name suggests, characterised by many conspicuous spots, which are scattered on the stems and on some of the leaves (2) (3). This species has both submerged leaves, which remain below the water, and floating leaves, which mass together on the surface (4).
The submerged leaves of the spotted pondweed are usually arranged alternately along the stem, and are narrow and lance-shaped, with wavy margins. These leaves are typically dark green, with a pair of smaller light to dark brown leaves, called stipules, at the base (2) (3) (5) (6). In comparison, the floating leaves of the spotted pondweed are usually light to dark green, oval-shaped and slightly indented at the base, with long black- or purple-spotted leaf stalks (2) (3) (5) (6) (7).
The inflorescences of the spotted pondweed are produced in dense spikes above the water, and each contains many small, inconspicuous flowers. The individual flowers have four small, greenish petals (2) (6) (7). The fruit of this species is olive to dark green or brown, rounded or oval-shaped, and has three prominent ridges on the outer surface (3) (4) (6) (8).