Nymphaea subg. Hydrocallis

'Nymphaea'' subg. Hydrocallis' is a subgenus of the genus Nymphaea''.

Vegetative characteristics
Species of Nymphaea subg. Hydrocallis are perennial, rhizomatous, aquatic herbs with contractile roots. The floating, petiolate leaves are orbicular to elliptic and have an entire margin.

Generative characteristics
The flowers are nocturnal and float on the water surface. The carpels have enlarged, clavate carpellary appendages. The flowers emit solvent-like, pungent, fermented, or fruity fragrances.

Publication
It was first described as Nymphaea sect. Hydrocallis Planch. by Jules Émile Planchon in 1853. Later, it was elevated to the status of the subgenus Nymphaea subg. Hydrocallis (Planch.) Conard by Henry Shoemaker Conard in 1905.

Species

 * Nymphaea amazonum Mart. & Zucc.
 * Nymphaea belophylla Trickett
 * Nymphaea caatingae C.T.Lima & Giul.
 * Nymphaea conardii Wiersema
 * Nymphaea francae C.T.Lima & Giul.
 * Nymphaea gardneriana Planch.
 * Nymphaea glandulifera Rodschied
 * Nymphaea harleyi C.T.Lima & Giul.
 * Nymphaea jamesoniana Planch.
 * Nymphaea lasiophylla Mart. & Zucc.
 * Nymphaea lingulata Wiersema
 * Nymphaea novogranatensis Wiersema
 * Nymphaea oxypetala Planch.
 * Nymphaea paganuccii C.T.Lima & Giul.
 * Nymphaea pedersenii (Wiersema) C.T.Lima & Giul.
 * Nymphaea potamophila Wiersema
 * Nymphaea prolifera Wiersema
 * Nymphaea rapinii C.T.Lima & Giul.
 * Nymphaea rudgeana G.Mey.
 * Nymphaea tenuinervia Casp.
 * Nymphaea vanildae C.T.Lima & Giul.

Distribution
The distribution of species within this subgenus extends from the southern United States through Central America, and the Caribbean to South America.