Nymphaeales
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Nymphaeales
Nymphaea lotus
Scientific classification
Kingdom: Plantae Division: Angiospermae Class: see text Order: Nymphaeales Dumortier
Families
Nymphaeaceae Cabombaceae Hydatellaceae

Nymphaeales is a botanical name at the rank of order. When recognized, it includes water lilies and sometimes other aquatic plants. This order is not part of the APG II system's 2003 plant classification (unchanged from the APG system of 1998), which instead has a broadly circumscribed family Nymphaeaceae (including Cabombaceae) unplaced in any order. It is recognized by some systems of plant taxonomy, but others use different placements for the families in this order. In particular some plant systematists using the APG II system now use this order and circumscribe it to include the Nymphaeaceae and Cabombaceae. A 2007 study has found that Hydatellaceae also belongs to this group.^[1]

This order is considered to be a basal, or early diverging, group of angiosperms. The families of this order are united by being families of aquatic herbs and are known from the fossil record as early as the Lower Cretaceous.

Fossils

The fossil record consists especially of seeds, and also pollen, stems, leaves, and flowers. It extends back to the Cretaceous.^[2][3]

It is posssible that the aquatic plant fossil Archaefructus belongs to this group.^[4]

Classification

The current phylogenetic placement (based on the APG II system, with subsequent revisions) is:

The family Cambombaceae is included within the Nymphaeaceae in the APG II system, but may optionally be recognized separately.

Cronquist

The Cronquist system, of 1981, placed it in subclass Magnoliidae, in class Magnoliopsida [=dicotyledons of division Magnoliophyta [=angiosperms]. It used this circumscription:

• order Nymphaeales

• family Nelumbonaceae
• family Nymphaeaceae
• family Barclayaceae
• family Cabombaceae
• family Ceratophyllaceae

Thorne (1992)

The Thorne system (1992) placed it in superorder Nymphaeanae in subclass Magnoliideae [=dicotyledons] in class Magnoliopsida [=angiosperms]. It used this circumscription:

• order Nymphaeales

• family Cabombaceae
• family Nymphaeaceae

Dahlgren

The Dahlgren system placed it in superorder Nymphaeanae, in subclass Magnoliideae [=dicotyledons], in class Magnoliopsida [=angiosperms]. It used this circumscription:

• order Nymphaeales

• family Cabombaceae
• family Nymphaeaceae
• family Ceratophyllaceae

References

1. ^ Saarela et al (2007). "Hydatellaceae identified as a new branch near the base of the angiosperm phylogenetic tree". Nature 446 (7133): 312–5. doi:10.1038/nature05612. PMID 17361182. 
2. ^ "Nymphaeales: Fossil Record". University of California Museum of Paleontology.
3. ^ Else Marie Friis, Kaj Raunsgaard Pedersen and Peter R. Crane (15 March 2001). "Fossil evidence of water lilies (Nymphaeales) in the Early Cretaceous". Nature 410: 357–360. doi:10.1038/35066557. PMID 11268209. 
4. ^ Soltis, D. E. (published June 2008). "The Year in Evolutionary Biology 2008". Ann. N.Y. Acad. Sci. 1133: 3–25. doi:10.1196/annals.1438.005. PMID 18559813. 

• Simpson, M.G. Plant Systematics. Elsevier Academic Press. 2006.