Nymphaea lotus f. thermalis

Nymphaea lotus f. thermalis (sometimes referred to as Nymphaea lotus var. thermalis)[1] is a form of Nymphaea lotus (commonly called the tiger lotus, white lotus or Egyptian white water-lily) in the genus Nymphaea.[2] Whilst some authorities list Nymphaea lotus f. thermalis as being synonymous with N. lotus,[3] others list it as a distinct taxon[4][5] – further investigation is required to determine its precise classification.[6] The usual habitat for Nymphaea lotus is the Nile Delta, hence Nymphaea lotus f. thermalis's Romanian habitat is unusual.[6]

Nymphaea lotus f. thermalis
Scientific classification
N. l. f. thermalis
Trinomial name
Nymphaea lotus f. thermalis


Nymphaea lotus f. thermalis is a water lily which blooms at night[6] – its flowers last four days and have four sepals, 19–20 white petals along with yellow anthers and stamens.[7] There is usually a 15–30 cm gap between flowers and the surface of the water, flowers are slightly fragrant; the round leaves of the plant are 20–50 cm wide.[7] A description was first formally published in Math. Természettud. Értes. 25(4):32, 36. 1907.[2]


Nymphaea lotus f. thermalis is endemic to the thermal water of the Peţa River, Sânmartin, Bihor County, Romania.[6] The area is protected as a nature reserve (51.0 hectares (126 acres) in size) and consists of a rivulet along with three ponds. The water has a roughly constant temperature of around 30 °C whilst the site has an average air temperature of 10–11 °C.[6] The thermal waters have been recorded as early as 1211, but it was only in 1799 that the first record of N. lotus was made, by Pál Kitaibel.[6][8] Janos Tuzson proposed in 1907 that this population's unusual location could be explained by the persistent heat provided by the thermal springs could have sustained the population at a pre-ice age time when the plant would have been spreading across the warmer regions of Europe; this theory was corroborated by additional evidence provided by the identification of other endemic species.[6][9] Alexandru Borza was the Government minister in charge of education (and also a botanist) who made the first push for legal protection and recognition of Nymphaea lotus f. thermalis – in 1932, the Cabinet of Romania declared the rivulet a nature reserve and the plant a "national monument".[6] Conservation action with the intent to preserve this population has been undertaken for many years (since at least 1940) – including the management of invasive species – and the plant has been included in recent water management legislation.[6]

Whilst not held in any Romanian botanical gardens, Nymphaea lotus f. thermalis is grown at Royal Botanic Gardens Kew and at the botanic garden of Bonn University.[6]


  1. ^ "Synonyms of Nymphaea lotus f. thermalis". Encyclopedia of Life. Archived from the original on 9 August 2014. Retrieved 9 August 2014.
  2. ^ a b "Nymphaea lotus f. thermalis". GBIF Backbone Taxonomy. GBIF. Archived from the original on 9 August 2014. Retrieved 9 August 2014.
  3. ^ "Nymphaea lotus f. thermalis". Germplasm Resources Information Network (GRIN). Agricultural Research Service (ARS), United States Department of Agriculture (USDA). Retrieved 9 August 2014.
  4. ^ "Nymphaea lotus f. thermalis". Encyclopedia of Life. Retrieved 9 August 2014.
  5. ^ "FORMA Nymphaea lotus f. thermalis". UniProt. Retrieved 9 August 2014.
  6. ^ a b c d e f g h i j Veler, Ana (November 2008). "Nymphaea lotus up north, naturally". Water Gardeners International. 3 (4). Retrieved 9 August 2014.
  7. ^ a b Courteau, Jacqueline. "Brief Summary of Nymphaea lotus L". Encyclopedia of Life. Retrieved 9 August 2014.
  8. ^ Waldstein, F. De Paula Adam Graf Von & P. Kitaibel (1799). "Descriptiones et icones plantarum rariorum Hungariae". Vienna. Cite journal requires |journal= (help)
  9. ^ Tuzson, János (1907). "A Nymphaea lotus csoport morfologiája és rendszertani tagolódása" (in Hungarian). Cite journal requires |journal= (help)