General: Aquatic or amphibious, perennial herb, rooting from nodes, roots slender, fibrous; stems slender, floating or trailing, smooth.
Leaves: Basal leaves absent; stem leaves kidney-shaped to broadly fan-shaped, deeply 3-lobed or 3-parted, 0.3-1.2 cm long, 0.5-2 cm wide, bases blunt to heart-shaped, the lobes undivided or the lateral cleft, the terminal segment entire or with small round teeth near tip, tips rounded; long-stalked; smooth.
Flowers: Inflorescence of solitary terminal and axillary flowers, long-stalked; receptacle smooth; petals 3 or 4, distinct, yellow, 2-4 mm long, 1-3 mm wide, egg-shaped, nectary on upper surface, the nectary scale partially covering nectary; sepals 3 or 4, spreading or bent back from base, 2-4 mm long, 1-3 mm wide, smooth; stamens 10-20; pistils 10-70.
Fruits: Achenes, several in a globe- to short egg-shaped head 3-5 mm long, 2-5 mm wide, the achenes egg-shaped, slightly flattened, 1-1.4 mm long, 0.8-1.2 mm wide, smooth; beaks persistent, curved, 0.1-0.4 mm long.
Ponds, muddy shores, and mossy seepage sites in thickets and forests in the montane zone; frequent in N BC, rare southward to 53degreeN, circumpolar, N to AK, YT and NT, E to Labr. and PQ and S to CO; Greenland, Iceland, N Eurasia.
The table below shows the species-specific information calculated from original data (BEC database) provided by the BC Ministry of Forests and Range. (Updated August, 2013)
