NELUMBONACEAE (lotus family)

One genus, 2 species, Northern Hemisphere, but in the Old World also south to Australia.

Traditionally (Steyermark, 1963), many botanists considered Nelumbo to represent a subfamily of the water lily family, Nymphaeaceae. Details of the flower and pollen morphology and the anatomy of the plants, as well as some aspects of phytochemistry, suggested that the two groups are not closely related and had been linked mostly because of the shared “water lily” growth form (Cronquist, 1981). However, where best to place the Nelumbonaceae within a classification of angiosperms has not fully been understood until recently. The current hypothesis (summarized in Judd et al., 2008) links the Nelumobonaceae loosely with two very different, woody families, the Platanaceae (sycamores and plane trees) and the Proteaceae (banksias, silk trees, and macadamia nuts). The three currently are considered to represent a separate order, Protealaes, which, in turn, appears to be loosely related to the Ranunculales (Berberidaceae, Menispermaceae, Papaveraceae, Ranunculaceae) and a few other families (Buxaceae, Trochodendraceae) at the base of the so-called eudicots (see Judd et al. [2008] for a summary). The Nelumbonaceae have a very long fossil history. As noted by C. L. Anderson et al. (2005), fossils from both the New and Old Worlds with the characteristic leaves and expanded receptacle date back to the early Cretaceous period (110 million years ago).