This is the most common species of Potamogeton in stagnant oligotrophic water across southeastern states, but there is no evidence of distinct varieties or definite hybrids (FNA 22). Floating leaves are typically 3-8.5 mm wide and have obtuse tips; with submerged leaves alone, colls. are often hard to identify. Plants with broader leaves and more acute tips, especially in flowing waters of major streams and rivers, should be compared with tennesseensis, which has been overlooked. See also spirillus.