Nymphaea atrans is a species of waterlily which is endemic to Queensland, Australia.
Description Vegetative characteristics Nymphaea atrans is a perennial plant with vertical, short, and swollen rhizomes. The leaf blades with toothed margins of 2mm long, regularly spaced teeth may reach 40 cm in width. The base of the petiole is winged.Jacobs, S. W. L. (1992). "New species, lectotypes and synonyms of Australasian Nymphaea (Nymphaeaceae)." Telopea, 4(4), 635-641.
Generative characteristics The flowers may rise up to 40 cm above the water level. Over time, the colour of Nymphaea atrans flowers shifts from blue and white to a deep pink.Standley, L. A. (1998). NEBC MEETING NEWS. Rhodora, 100(901), 92–95. http://www.jstor.org/stable/23313273 Gilman, A. V., & Padgett, D. J. (2002). NEBC MEETING NEWS. Rhodora, 104(920), 434–438. http://www.jstor.org/stable/23313515 Each flower has ca. 300 stamens with 14 mm long, cylindrical to membranous filaments. The anthers, typically featuring a small hooked apical appendage, can reach up to 10 mm in length.
Cytology The nuclear genome size is 1408.32 Mb, and the chromosome count is n = 42.Chen, F., Liu, X., Yu, C., Chen, Y., Tang, H., & Zhang, L. (2017). "Water lilies as emerging models for Darwin’s abominable mystery." Horticulture research, 4. The chloroplast genome is 160,990 bp long.
Reproduction Generative reproduction Flowering occurs from July to November.
Natural hybridisation Natural hybrids of Nymphaea atrans with Nymphaea immutabilis with reduced fertility have been reported from areas of sympatric occurrence. Apart from the reduced fertility, the hybrids can be identified through the lighter pink colouration of older flowers, as they do not darken to the darker shades found in Nymphaea atrans. It was reported that in one hybrid population most individuals do not exhibit the characteristic shift in floral colouration. Additionally, even those that do exhibit this characteristic shift do not reliably produce offspring with the same trait from seed.Magdalena, C. (2009, November). New Species and Hybrids for the Royal Botanic Gardens, Kew. WGI Online Journal. Retrieved December 26, 2023, from http://www.watergardenersinternational.org/journal/4-4/carlos/gallery1.html
Taxonomy It was first described by Surrey Wilfrid Laurance Jacobs in 1992.
Type specimen The type specimen was collected by Surrey Wilfrid Laurance Jacobs and J. Clarkson along the Bathurst Bay road north of Wakooka in Queensland, Australia on the 31st of July 1987.
Placement within Nymphaea It is placed in Nymphaea subgenus Anecphya.Borsch, T., Hilu, K. W., Wiersema, J. H., Löhne, C., Barthlott, W., & Wilde, V. (2007). Phylogeny of Nymphaea (Nymphaeaceae): Evidence from Substitutions and Microstructural Changes in the Chloroplast trnT‐trnF Region. International Journal of Plant Sciences, 168(5), 639–671. https://doi.org/10.1086/513476Wei, Q., Liu, A. C., Chen, C., Lu, Y., Zhang, Y., & Li, S. J. (2023). "The complete chloroplast genome of Nymphaea atrans (Surrey Wilfrid Laurance Jacobs, 1992: Nymphaeaceae)." Mitochondrial DNA Part B, 8(3), 430-433.
It is close to Nymphaea immutabilis. Despite morphological differences, a molecular study was unable to differentiate both species based on the nuclear marker ITS, as well as the chloroplast marker trnT-trnF.Löhne, C., Borsch, T., Jacobs, S. W., Hellquist, C. B., & Wiersema, J. H. (2008). "Nuclear and plastid DNA sequences reveal complex reticulate patterns in Australian water-lilies (Nymphaea subgenus Anecphya, Nymphaeaceae)." Australian Systematic Botany, 21(4), 229-250.
Etymology The specific epithet atrans is derived from the Latin "atrans", meaning darkening, which references the shift of floral colouration from blue and white to a deep pink in ageing flowers.
Conservation The NCA status of Nymphaea atrans is Special Least Concern.
Ecology Habitat It occurs in the Cape York Peninsula of northern Queensland, Australia.Hedemark, N. (2010, May). Nymphaea subgenus Anecphya What We Know Today. WGI Online Journal. Retrieved December 26, 2023, from http://www.watergardenersinternational.org/journal/5-2/nimai/page1.html It occurs in Billabongs, lakes, and former pastoral dams on floodplains.
Cultivation Because of its outstanding, showy ornamental qualities, this species is grown in waterscape gardens globally and is well-suited for use as display plants in water gardens.Singapore Government. (n.d.). Nymphaea atrans S.W.L.Jacobs. NParks Flora & Fauna Web. Retrieved December 26, 2023, from https://www.nparks.gov.sg/florafaunaweb/flora/8/7/8731 It has been used in the creation of several new Nymphaea hybrids.Parents for Nymphaea hybrids - IWGS Plant Database. (n.d.). Retrieved December 26, 2023, from https://plants.iwgs.org/Home/FertilityList
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