- Group 1Lycophytes, Monilophytes
- Group 2Gymnosperms
- Group 3Monocots
- Group 4Woody angiosperms with opposite or whorled leaves
- Group 5Woody angiosperms with alternate leaves
- Group 6Herbaceous angiosperms with inferior ovaries
- Group 7Herbaceous angiosperms with superior ovaries and zygomorphic flowers
- Group 8Herbaceous angiosperms with superior ovaries, actinomorphic flowers, and 2 or more distinct carpels
- Group 9Herbaceous angiosperms with superior ovaries, actinomorphic flowers, connate petals, and a solitary carpel or 2 or more connate carpels
- Group 10Herbaceous angiosperms with superior ovaries, actinomorphic flowers, distinct petals or the petals lacking, and 2 or more connate carpels
The flowers of Nuphar are interesting. The outer whorl of perianth is composed of 5 or 6 petaloid sepals. The inner whorl of perianth is represented by many small, thick structures that are transitional in appearance to the stamens. Beal (1956) placed all our species as infraspecific taxa under Nuphar lutea, a European plant. Subsequent studies have shown that our species are distinct from N. lutea. However, further research is needed to determine the correct placement of N. microphylla, which appears to be closely related to the Eurasian N. pumila (Timm) DC. (and was synonymized under the latter name by Beal). References: Wiersema and Hellquist (1997), Hellquist and Crow (1984).
1a. Sepals 1–2.5 cm long, numbering 5 per flower; anthers predominantly shorter than the filaments, 1–3 mm long; fruit strongly constricted below the red stigmatic disk; petals and stamens promptly deciduous, usually not persisting as remnants at the base of the fruit; basal sinus of leaf blade (42–) 54–90% of the length of the blade midrib [Fig. 54]
1b. Sepals 2.5–5 cm long, numbering 6 per flower; anthers longer than the filaments, 3–9 mm long; fruit only slightly constricted below the green (rarely red) stigmatic disk; petals and stamens tardily deciduous, usually persisting as remnants around the base of the fruit; basal sinus of leaf blade 30–59 (–62)% of the length of the blade midrib [Fig. 55]
Show photos of: Each photo represents one species in this genus.