Nuphar lutea

Nuphar lutea, the yellow water-lily, brandy-bottle, or spadderdock, is an aquatic plant of the family Nymphaeaceae, native to northern temperate and some subtropical regions of Europe, northwest Africa, and western Asia. This species was used as a food source and in medicinal practices from prehistoric times with potential research and medical applications going forward.

Description


F. G. Hayne's Faithful Representation and Description of the Plants Used in Medicine published in 1813 offered an illustration of Nuphar latea "in its natural size" centered on its large crown leaf, several emerging leaflets from the plant's root system (rhizome), and its distinctive yellow flower set on a stem above the water surface. The copper plate from this early botanical treatise adds the following details: Figures 3 and 4, the male fertilizing organ (stamen) composed of filaments capped by pollen-containing anthers; Figures 5 and 6, the flower's female reproductive part (pistil), containing a cup-like ovary topped by pollen-receptive tip (stigma), whole and cut lengthwise; Figures 7 and 8, the mature berry (ovule) protected by outer petals and sepals, whole and sliced; and Figures 9 through 12, the mature berry holding seed, natural size and enlarged, then sliced on two axes. The pollen grain photographed here is a 30.70 μm (micrometer) yellow sphere of prickly (echinate) ornamentation with well-developed spines indicating "primitive phylogenetic position of the genus [Nuphar] as well as for Nymphaeaceae [lily family]."

Nuphar lutea flowers emerge about three years after seed germination, blooming mid-spring through early autumn, each flower taking 4 to 5 days to develop – a process incorporating secretion of a sweet-smelling nectar on the stigma, pollen cross-fertilization by a host of insects (bees, beetles, flies, aphids), expansion of the female reproductive parts (gynoecium) up to three times in diameter, birthing as many as 400 seeds, and finally dispersal of the seeds on the water surface as the seed-head bursts, spreading them up to 80 m/h (meters/hour) over a 72-hour period before they sink to the bottom.

The flower is solitary, terminal, held above the water surface; it is hermaphrodite, 2–4 cm diameter, with five or six large bright yellow sepals and numerous small yellow petals largely concealed by the sepals. Flowering is from June to September, and pollination is entomophilous, by flies attracted to the alcoholic scent. The flower is followed by a green bottle-shaped fruit, containing numerous seeds which are dispersed by water currents.

New plants or colonies of Nuphar lutea can also be generated by the root system pictured in the illustration, described as follows: "Branching, spongy, tuberous rhizomes 20–150 mm in diam., firmly attached to the substrate [lake floor], dense tangled hairs around leaf scars." New flower stalks and leaves – submerged and floating on the surface – continually emerge on the growing network of rhizomes. The common name "spadderdock" comes from spattered seed when the fruit bursts, the common name "brandy bottle" from the aroma produced by the flowers which is similar to stale alcohol.

Publication
It was first described by Carl Linnaeus as Nymphaea lutea L. in 1753. Later, it was transferred to genus Nuphar Sm. as Nuphar lutea (L.) Sm. by James Edward Smith in 1809.

Species delimitation
Some botanists have treated Nuphar lutea as the sole species in Nuphar, including all the other species in it as subspecies and giving the species a holarctic range, but the genus is now more usually divided into eight species (see Nuphar for details).

Etymology
The specific epithet lutea, from the Latin luteus, means yellow.

Habitat
Habitat for Nuphar lutea ranges widely from moving to stagnant waters of "shallow lakes, ponds, swamps, river and stream margins, canals, ditches, and tidal reaches of freshwater streams"; alkaline to acidic waters; and sea level to mountainous lakes up to 10,000 feet in altitude. The species is less tolerant of water pollution than water-lilies in the genus Nymphaea. This aquatic plant grows in shallow water and wetlands, with its roots in the sediment and its leaves floating on the water surface; it can grow in water up to 5 metres deep. It is usually found in shallower water than the white water lily, and often in beaver ponds. Since the flooded soils are deficient in oxygen, aerenchyma in the leaves and rhizome transport oxygen from the atmosphere to the rhizome roots. Often there is mass flow from the young leaves into the rhizome, and out through the older leaves. This "ventilation mechanism" has become the subject of research because of this species' substantial benefit to the surrounding ecosystem by "exhaling" methane gas from lake sediments.

Herbivory
Nuphar lutea plant colonies in turn are affected by organisms that graze on its leaves, gnaw on stems, and eat its roots, including turtles, birds, deer, moose, porcupines, and more. The rhizomes are often consumed by muskrats. The waterlily leaf beetle, Galerucella nymphaeae, spends its entire life cycle around various Nuphar species, exposing leaf tissue to microbial attack and loss of floating ability.

With other species in the Nymphaeales order, Nuphar lutea provides habitat for fish and a wide range of aquatic invertebrates, insects, snails, birds, turtles, crayfish, moose, deer, muskrats, porcupine, and beaver in shallow waters along lake, pond, and stream margins across the multiple continents where it is found.

Distribution and habitat
Nuphar lutea is native to the region spanning from Europe to Siberia, Xinjiang, China, and North Algeria. It is extinct in Sicily, Italy. It has been introduced to Bangladesh, New Zealand, and the Russian region Primorye.

Conservation status
The IUCN conservation status is Least Concern (LC).

Food
Nuphar lutea is used as food.

Symbolism
Stylized red leaves of the yellow water lily, known as seeblatts or pompeblêden are used as a symbol of Frisia. The flag of the Dutch province of Friesland features seven pompeblêden. Stone masons carved forms of the flowers on the roof bosses of Bristol Cathedral and Westminster Abbey, these are thought to encourage celibacy.