Whorled Marsh Pennywort is a delicate, low-growing plant that creates a miniature landscape on muddy shorelines and in shallow water. Its defining feature is its perfectly round leaves, which look like tiny green parasols or lily pads held aloft on thin stems attached directly to the center.

True to its name, these leaves emerge in distinct whorls from creeping runners that root in the mud, forming a lush, interconnected carpet. Inconspicuous greenish-white flowers also appear in these whorls, often hidden beneath the leaves. This plant provides excellent cover for tadpoles, small fish, and aquatic insects.