Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 8/7/2001
Publication Date: N/A
Technical Abstract: Nymphaea (the waterlilies) is the most diverse genus (45 species) of the order Nymphaeales, which is congruently inferred as the second branch of the angiosperm tree. In a collaborative effort, several genomic regions (trnT-F, trnK-intron including matK, ITS1-5.8S-ITS2; approx. 5000 bp) were sequenced from nearly all species. In contrast to previous classifications a BAN-clade is hypothesized within Nymphaea, comprising the subgenera Brachyceras (pantropical) and Anecphya (australasian) in a terminal lineage sister to the temperate subgen. Nymphaea. A second major lineage includes an assemblage of the SE-African N. petersiana with the subgenera Lotos and Hydrocallis. Based on a synopsis of the fossil record the earliest known appearance of Nymphaea is Middle Eocene (45 MYBP). Combining palaeobotanical and molecular evidence it seems that a rapid early differentiation into the major clades is contrasted by comparatively recent species diversifications within these clades. In the case of the temperate subgen. Nymphaea-clade which comprises closely related circumboreal taxa (pygmy waterlilies) as well as species confined to either North America or Europe, possible patterns of spatial differentiation are discussed.