Nymphaea

Water lilies live in fresh water.

Their leaves float on the top. Some leaves stay under the water. They have many bright flowers.

These flowers can open in the day. Some flowers open at night. Beetles and bees visit the flowers. This helps the plants grow. The leaves also make shade. This shade helps the pond stay healthy.

Water lilies are very special plants.

Water lilies are plants that live in fresh water.

People often grow them to make ponds look pretty. Their leaves mostly float on the water. Some leaves stay under the water. These leaves can be small or very big. Some leaves grow up to 60 cm wide.

Water lilies have many colorful flowers. Some flowers open during the day. Others open at night. Many flowers use insects to help them grow. For example, some use bees or flies. Others use beetles.

These plants have parts called rhizomes. A rhizome is a thick stem that grows under the water. It can be branched or plain. The plants also have seeds and fruit. Some people have used these plants for food. In some places, they eat the seeds or the tubers. A tuber is a thick, round part of the root.

However, be careful! All water lilies are poisonous. They contain a substance called nupharin. This can make you sick if you eat it.

Water lilies are beautiful plants that live in fresh or brackish water.

You might know them as Nymphaea, a name from Greek and Latin mythology. These plants are found all over the world. Many people grow them in gardens to look pretty. Some types can even become weeds if they are not native.

They are very helpful in ponds because their leaves provide shade. This shade helps stop too much algae from growing.

These plants have a very interesting way of growing. Most of their leaves float on top of the water. However, some leaves stay under the water or poke out.

The leaves come in many shapes like circles or hearts. They can be small or as wide as 60 cm. Under the water, the plants have thick stems called rhizomes. These rhizomes can be branched or plain. They also have roots that can pull themselves deeper into the mud.

The flowers of the water lily are quite special too. They can grow above the water or float on it. Some flowers open during the day, while others open at night.

Most flowers have green sepals and many colorful petals. They can have between 6 and 50 petals. Inside, there are often many stamens, which are the parts that make pollen. Some flowers use insects to help them make seeds. For example, beetles, bees, and flies all visit them.

Humans have studied these plants for a long time. Carl Linnaeus described the genus Nymphaea in 1753. Since then, scientists have found many different types. As of January 2024, there are 65 accepted species. Some species are very rare and in danger of disappearing. For instance, Nymphaea thermarum is considered critically endangered. Scientists also look at their cells to study their chromosomes.

Even though they are pretty, you must be careful with them. All water lilies are poisonous because they contain nupharin.

This is a substance called an alkaloid. Some people in places like India or West Africa have used them for food. They might eat the seeds or the tubers, which are thick root parts. In the Philippines, people have also used them. In North America, some people eat the young leaves. It is important to know how they are prepared safely.

The genus *Nymphaea* consists of diverse aquatic plants known commonly as water lilies.

These plants belong to the family Nymphaeaceae and have a cosmopolitan distribution. This means they are found across many different parts of the world. They live in both freshwater and brackish water habitats. Many people grow these plants for their beauty in gardens. However, some species can become invasive weeds when introduced to new areas.

The name *Nymphaea* comes from Greek and Latin mythology. It was inspired by the nymphs found in those ancient stories.

Water lilies have complex structures that allow them to thrive in water. They are perennial or annual herbs with specialized underground parts. These plants often possess rhizomes, which are thick, horizontal underground stems. Some rhizomes are branched, while others are unbranched or stoloniferous. The plants also have tuberous or fibrous roots that are contractile. This means the roots can pull the plant deeper into the substrate. Most leaves are floating, but some species have submerged or emergent leaves. The leaf shape, or lamina, can be many things like ovate or orbicular. The width of these leaves can range from 2.5 cm to 60 cm.

The reproductive parts of the plant are equally intricate. The flowers can be emergent, floating, or occasionally submerged. They are often hermaphrodite, meaning they have both male and female parts. Most flowers are protogynous, which is a process where the female parts mature before the male parts. This helps manage how the plant reproduces.

The flowers typically have four or five green sepals. They can have between 6 and 50 colorful petals. The androecium, or male part, consists of 20 to 750 stamens. The gynoecium, or female part, contains 5 to 35 carpels. These carpels develop into a fleshy, spongy fruit that carries the seeds.

Pollination is a vital process for the survival of different subgenera. Different insects have evolved to interact with specific types of water lilies. For example, species in the subgenus *Hydrocallis* are pollinated by *Cyclocephala* beetles.

Other groups, like subgenus *Brachyceras*, rely on bees and flies for pollination. The subgenus *Nymphaea* uses a mix of bees, flies, and beetles. This variety in pollination ensures that different species can continue to grow. Some species even produce proliferating pseudanthia, which are specialized structures used for vegetative propagation.

Humans have a long history of studying and classifying these plants. The genus *Nymphaea* was formally described by Carl Linnaeus in 1753.

Since then, many scientists have contributed to our understanding. Richard Anthony Salisbury published the synonym *Castalia* in 1805. Otto Kuntze published *Leuconymphaea* in 1891, and Cornelis den Hartog published *Ondinea* in 1970. As of January 2024, there are 65 accepted species recognized by Plants of the World Online. This includes the type species, *Nymphaea alba*. Scientists also study their cytology, or cell biology, noting chromosome counts from 28 to 224.

While beautiful, these plants play significant roles in their ecosystems. In ponds and lakes, the floating leaves provide shade. This shade is helpful because it reduces the growth of algae. However, some species can cause problems if they become invasive. In South Africa, *Nymphaea mexicana* has become an invasive weed.

Scientists have even proposed using the weevil *Bagous longulus* as a biological control agent. It is also important to protect rare species. Some lilies are in danger of disappearing forever. For example, *Nymphaea thermarum* is classified as critically endangered.

Water lilies also have a complex relationship with human use. All species contain an alkaloid called nupharin, which makes them poisonous.

Despite this toxicity, some cultures have used them as food. In India, they have been used as famine food or medicine. In West Africa, people have ground rhizomes into flour. Some indigenous Australians in the 1930s ate the flowers and stems raw. This shows how deeply these plants are connected to human history and survival across the globe.