Nymphaea immutabilis

Nymphaea immutabilis
Flowering Nymphaea immutabilis at Mount Carbine, Queensland, Australia
Conservation status
Special Least Concern  (NCA) [1]
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Order:	Nymphaeales
Family:	Nymphaeaceae
Genus:	Nymphaea
Subgenus:	Nymphaea subg. Anecphya
Species:	N. immutabilis
Binomial name
Nymphaea immutabilis S.W.L.Jacobs [2]
Nymphaea immutabilis is native to Western Australia, the Northern Territory, and Queensland, Australia [2]
Synonyms [2]
Nymphaea lotus var. australis F.M.Bailey

Nymphaea immutabilis (black-soil waterlily) is a species of waterlily native to the far north of Western Australia, the Northern Territory, and northern and eastern Queensland, Australia. ^{[3] [2]}

Description

Vegetative characteristics

Nymphaea immutabilis is an annual or perennial plant with globose rhizomes. ^[4] The round, 70 cm wide leaves have dentate margins. ^{[5] [4]}

Generative characteristics

The flowers are up to 30 cm in diameter, on pedicels or stalks up to 5 m long; ^[6] the outer petals are blue, grading to white inner petals. ^[7] The flowers extend up to 50 cm above the water surface. ^[5] The flowers have four sepals, and 34 petals. The androecium consists of 400 stamens. The gynoecium consists of 9-20 carpels. ^[4] The globose, 5 cm wide fruit bears numerous 4 mm long, and 2.5 mm wide, rounded seeds with trichomes arranged in irregular rows. ^[5] The immature seeds are red, but mature to brownish-grey. ^[8] The seeds have a mechanism of physiological dormancy. ^[9]

Cytology

The chromosome count is n = 42. The genome size is 1408.32 Mb. ^[10]

Reproduction

Generative reproduction

Flowering occurs from March to November. ^{[5] [4]}

Taxonomy

Publication

It was first described by Surrey Wilfrid Laurance Jacobs in 1992. ^[2]

Type specimen

The type specimen was collected by S. Jacobs and J. Clarkson near Mareeba, Queensland, Australia on the 26th of July 1987. ^[4]

Placement within Nymphaea

It is placed in Nymphaea subgenus Anecphya. ^[9]

Separation of Nymphaea kimberleyensis

The subspecies Nymphaea immutabilis subsp. kimberleyensis S.W.L.Jacobs was described in 1992. Later in 2011, it was elevated to a separate species Nymphaea kimberleyensis (S.W.L.Jacobs) S.W.L.Jacobs & Hellq. ^{[11] [12]}

Etymology

The specific epithet immutabilis, meaning unchanging, references the floral colouration, which does not change as the flower ages. ^[4]

Conservation

The NCA status of Nymphaea immutabilis is Special Least Concern (SL). ^[1] In the Northern Territory it is categorised as vulnerable. ^{[13] [14]}

Ecology

Habitat

It occurs in swamps, ^[9] permanent, or temporary waters, ^[4] billabongs, streams, and rivers. ^[8]

References

1. Queensland Government. (2022e, March 8). Species profile — Nymphaea immutabilis. Retrieved 2 January 2024, from https://apps.des.qld.gov.au/species-search/details/?id=21929
2. "Nymphaea immutabilis S.W.L.Jacobs". Plants of the World Online . Royal Botanic Gardens, Kew . Retrieved 2 January 2024.
3. "Species: Nymphaea immutabilis (Black-soil Waterlily)". Atlas of Living Australia. 1992-03-12. Retrieved 2025-07-13.
4. Jacobs, S. W. L. (1992). "New species, lectotypes and synonyms of Australasian Nymphaea (Nymphaeaceae)." Telopea, 4(4), 635-641.
5. Stephens, K. M., Dowling, R. M. (2002). "Wetland Plants of Queensland: A Field Guide". p. 56. Kokosinsel (Keeling): CSIRO Publishing.
6. Lane-Poole, C.E. (1925). The Forest Resources of the Territories of Papua and New Guinea. Melbourne: Australian Government. p. 86.
7. "Nymphaea immutabilis subsp. immutabilis". International Waterlily Collection. Retrieved 2025-07-13.
8. Dalziell, E. L. (2016). "Seed biology and ex situ storage behaviour of Australian Nymphaea (water lilies): implications for conservation (Doctoral dissertation, PhD thesis. University of Western Australia, Perth, WA)".
9. Dalziell, E. L., Baskin, C. C., Baskin, J. M., Young, R. E., Dixon, K. W., & Merritt, D. J. (2019). "Morphophysiological dormancy in the basal angiosperm order Nymphaeales." Annals of botany, 123(1), 95-106.
10. 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.
11. Jacobs, S. W., & Hellquist, C. B. (2011). "New species, possible hybrids and intergrades in Australian Nymphaea (Nymphaeaceae) with a key to all species." Telopea, 13(1-2), 233-243.
12. "Nymphaea kimberleyensis (S.W.L.Jacobs) S.W.L.Jacobs & Hellq". Plants of the World Online . Royal Botanic Gardens, Kew . Retrieved 2 January 2024.
13. White, M., Albrecht, D., Duguid, A., Latz, P., & Hamilton, M. (2000). "Plant species and sites of botanical significance in the southern bioregions of the Northern Territory. Volume 1: significant vascular plants."
14. Fisher, A., Baker, B., & Woinarski, J. (2002). "Mitchell Grass Downs, Northern Territory."