F. H. Utech (1978, 1979) clearly demonstrated the relationship of Pleea to Tofieldia sensu lato and reassigned the only species of the former to the latter. Morphologically, though, P. tenuifolia is a very distinctive species and, while it shares characteristics with both Tofieldia and Triantha, it is not in any way an intermediate.
This project was made possible in part by the Institute of Museum and Library Services [MG-70-19-0057-19].