Ranunculus confervoides

Ranunculus confervoides, sometimes treated as a northern segregate of the white water-crowfoot complex, is an aquatic perennial herb in the Ranunculaceae family. It grows submerged or partly emergent in shallow, cold, still or slow-moving waters of arctic and subarctic lakes, ponds, and pools, often on muddy or sandy substrates. Stems are slender, flexuous, branching, and may extend up to 30 to 50 centimetres in length. The leaves are all submerged and finely dissected into thread-like, capillary segments that collapse out of water, an adaptation that maximises surface area for gas exchange in cold waters. Small white flowers, about 6 to 10 millimetres across, sit on slender peduncles just at or above the water surface; each has five white petals with a yellow basal nectary and numerous stamens and pistils. Achenes are small, plump, and finely transversely wrinkled. The species is circumboreal in distribution.