Nomenclature
Scientific Name:
Nuphar lutea (L.) Sm. in Sibthorp & Smith, Fl. Graec. Prodr. 1, 361 (1809)
Synonymy:
  • Nymphaea lutea L., Sp. Pl. 510 (1753)
Etymology:
Named for the flower colour luteus (Latin) or yellow.
Vernacular Name(s):
brandy bottle; yellow water lily
 Description

Perennial, aquatic herb, with branching, spongy, tuberous rhizomes 20–150 mm in diam., firmly attached to the substrate, dense tangled hairs around leaf scars. Roots adventitious. Leaves weakly dimorphic, floating and submerged; floating leaves on long, stout, trigonous petioles; lamina 120–300 × 90–220 mm, broadly elliptic to ovate, cordate, coriaceous, green to dark purple below, glabrescent, margin entire; submerged leaves on thin, short petioles, lamina thin and semi-translucent (larger than emergent leaves). Flowers 30–65 mm in diameter, solitary, subglobose, with 2 whorls of tepals, outer whorl petaloid, inner whorl stamen-like, held above the water on stout terete peduncles 4–8 mm in diameter; stale alcoholic scented. Outer tepals 5(–6), 20–30 mm long, broadly obovate, apices rounded, yellow with green towards the base. Inner tepals 11–20, 7.5–23 mm long, obovate, apices rounded, with abaxial yellow nectaries. Stamens numerous, 11–12 mm long, anthers yellow. Ovary 26–45 × 20–35 mm, smooth to furrowed, neck prominent, capped by a slightly lobed to entire stigmatic disc 7–13 mm in diameter, 5–20 stigmatic rays. Fruit 26–60 × 20–35 mm, urceolate, neck prominent, glabrous, smooth to slightly furrowed, yellowish-green, dehiscent from the base. Seeds up to 400, 3.5–5 × 3–3.5 mm, ovoid, smooth, shiny, olive-green to pale yellow. Dispersal hydrochory.

 Taxonomy

Nuphar lutea in the narrow sense of Padgett (2007) is followed rather than Beal’s (1956) broad concept, which recognised nine subspecies encompassing all European and North American taxa.

 Recognition

Distinguished from species of Nymphaea by more heart-shaped leaves, globose-shaped yellow flowers (with firm tepals) that appear half open, and a greenish, urceolate-shaped fruit capped by a hard, flattish disc that matures above the water surface rather than below. Also, Nuphar lutea has a distinctive, large, spongy rhizome compared with the rhizomes of Nymphaea species and also other attached-floating aquatics such as Hydrocleys nymphoides (water poppy) and species of Nymphoides (marshwort, fringed water lily). The flowers are said to smell of alcohol and N. lutea is sometimes known as brandy-bottle, a reference to the smell and the flask-shaped ovary (Garnock-Jones 1988).

 Distribution

North Island: Southern North Island – Hawke’s Bay, Horseshoe Lake, near Patangata (targeted for eradication, with no plants seen since 2013).

South Island: Canterbury – Hazelburn Creek, Tōtara Valley, near Pleasant Point (targeted for eradication).

Occurs naturally in Eurasia (sea level to approx. 850 m a.s.l.).

 Habitat

Growing in shallow waters of ponds, lakes, canals, wetlands and the margins of slow-flowing streams and rivers.

 Biostatus
Exotic
 First Record

CHR 119711, R. Mason, 21 Jan 1961, Horseshoe lake, near Patangata, Hawke's Bay.

 Phenology

Flowering: Nov.–Jan.; fruiting: Aug.

 Notes

Large, tuberous rhizomes which overwinter, sending up new leaves in spring. Fruits develop above the water surface on decaying peduncles, with the outer tepal whorl often remaining attached to the mature fruit. According to Smits et al. (1989, 1990) the seeds are not buoyant, have a poor ability to withstand desiccation, and produce a transient seed bank whereby few viable seeds are present in the sediment between the end of the germination period and the next seed release. Evidence suggests (Schoelynck et al. 2014) that the larger, semi-translucent submerged leaves play a role in reducing flow velocities and promoting sedimentation.

Other species recorded in cultivation in New Zealand but not naturalised are: N. advena, N. pumila and N. variegata (Nichol 1997; Parsons et al. 1997).

 Bibliography
Beal, E.O. 1956: Taxonomic revision of the genus Nuphar Sm. of North America and Europe. Journal of the Elisha Mitchell Scientific Society 72: 317–346.
Biosecurity New Zealand 2012: Regional Pest Management Strategies Database. http://www.biosecurityperformance.maf.govt.nz/
Biosecurity New Zealand 4 Aug 2011: Unwanted Organisms Register. http://www.biosecurity.govt.nz/pests/registers/uor
Biosecurity New Zealand 2008: National Plant Pest Accord. MAF Biosecurity New Zealand, Wellington.
Ford, K.A.; Champion, P.D. 2019: Nymphaeales. In: Breitwieser, I.; Wilton, A.D. (ed.) Flora of New Zealand - Seed Plants. Fascicle 5. Manaaki Whenua Press, Lincoln.
Garnock-Jones, P.J. 1988: Nymphaeaceae. In: Webb, C.J.; Sykes, W.R.; Garnock-Jones, P.J. Flora of New Zealand. Vol. IV. Naturalised Pteridophytes, Gymnosperms, Dicotyledons. Botany Division DSIR, Christchurch. 871–873.
Linnaeus, C. 1753: Species Plantarum. Impensis Laurentii Salvii, Stockholm.
Ministry for Primary Industries 23 Feb 2017: Unwanted Organisms Register. Version 02.01.02. https://www1.maf.govt.nz/uor
Nichol, E.R. 1997: Vascular plant species recommended for ‘Entry Prohibited’ status. Biodiversity and Conservation, Landcare Research New Zealand Ltd.
Padgett, D.J. 2007: A monograph of Nuphar (Nymphaeaceae). Rhodora; Journal of the New England Botanical Club. 109(937): 1–95.
Parsons, P.; Smithies, V.; Trigg, L. 1997: Plant survey. Federation of New Zealand Aquarium Societies, Napier, New Zealand.
Schoelynck, J.; Meire, P.; Bal, K.; Verschoren, V.; Temmerman, S.; Penning, E.; Struyf, E.; Bouma, T.; Meire, D. 2014: Different morphology of Nuphar lutea in two contrasting aquatic environments and its effect on ecosystem engineering. Earth surface processes and landforms Published online in Wiley Online Library (wileyonlinelibrary.com) DOI: 10.1002/esp.3607
Sibthorp, J.; Smith, J.E. 1806-1809: Florae Graecae Prodromus. Vol. 1. Richardi Taylor et Socii, London.
Smits, A.J.M.; van Avesaath, P.H.; van der Velde, G. 1990: Germination requirements and seed banks of some nymphaeid macrophytes: Nymphaea alba L., Nuphar lutea (L.) Sm., and Nymphoides peltata (Gmel.) O.Kuntze. Freshwater Biology 24: 315–180.
Smits, A.J.M.; van Ruremonde, R.; van der Velde, G. 1989: Seed dispersal of three nymphaeid macrophytes. Aquatic Botany 35: 167–180.