Ranunculus trichophyllus

This record represents the narrower concept of Ranunculus trichophyllus, not including R. codyanus, R. confervoides, and R. porteri, following Wiegleb et al. (2017) and accepted in Weakley et al. (2025). In contrast, Kartesz (1994) recognized R. trichophyllus (with var. eradicatus including R. codyanus and R. confervoides,and var. trichophyllus including R. porteri). Also differing, FNA (vol. 3, 1997) recognized R. aquatilis (with var. aquatilis, and a very broad var. diffusus distinguished that included R. trichophyllus in synonymy). Wiegleb et al. (2017) state the following regarding the distribution of R. trichophyllus. "It occurs in North and South America, Greenland, Europe, Asia except Japan, North and South Africa, Australia, Tasmania and New Zealand. It is a frequent species of rivers, ponds and lakes, in particular in alkaline waters" (Wiegleb et al. 2017).