132021 PERFOLIATE PONDWEED Potamogeton perfoliatus (Potamogetonaceae) Aquatic. Freshwater perennial that grows in still or slow-flowing waters. FLOWERS are borne in small, few-flowered spikes (Jun-Sep). FRUITS are rounded. LEAVES are all submerged, dark green and translucent; they are oval, tapering and unstalked, with heart-shaped bases that clasp the stem. STATUS-Widespread and locally common.