........5 Leaf segments flat (at least near the nodes, but usually throughout); midvein visible; mid-stem leaves with (8-) 10-16 nodes per rachis; longest primary segments with 9-22 secondary segments; leaf shape in outline deltoid or trowel-shaped, the leaf segments becoming progressively and noticeably shorter towards the leaf apex; styles (0.8-) 1.0-2.0 mm long, slightly to distinctly spreading; flowering Jul-Oct; fruiting mid Jul-Oct; [of bottomlands, swamps, pond margins]