20 Captivating Colorful Sea Plants, 2024

We have always seen plants around us and admired their beauty, colors, and different types. They always mesmerize us with their beauty, patterns, and many more.

Here we are today to learn a little about such a plant but in water. Interesting right? To know more about sea plants, which make the underwater even prettier.

20 Captivating Colorful Sea Plants

1. Sea Brush

Scientific name Odonthalia floccosa
Color Present Dark red or brownish-black
Identification Highly branched perennial seaweed

The red seaweed is highly branched, with small clusters of branchlets that give it a tufted look. They grow up to 40 cm in height. This sea plant is found on rocks in the low intertidal of semi-exposed and semi-protected habitats in the North Pacific.

The branching of this red sea plant occurs alternately and in one plane, giving it a flattened appearance. Sea brush frequently hosts epiphytic algae such as sea cauliflower.


2. Polysiphonia atlantica

Scientific name

Polysiphonia atlantica

Color Present Red
Identification Small red filamentous algae

The red sea plant grows only up to 3cm in height, and it is usually reddish brown in color. The algae have many erect branches, which all grow to similar lengths.

The red sea plant is commonly found growing on rocks, mussels, other invertebrates, or epiphytes. They are native to the Atlantic and Indo-Pacific Oceans.

The red algae has three stages in its life cycle.


3. Sargassum filipendula

Scientific name Sargassum filipendula
Color Present Brown
Identification brownish with thin branches

The sea plant is the source of bioactive compounds with antioxidant and matrix metalloproteinases. These algae are also used for composting and manuring.

The brown algae can grow up to 50cm long with their branch extending. They spread from Florida, and the Caribbean to Brazil, abundant in reefs, coastal shallows, and mangroves.


4. Limu Kohu

Scientific name Asparagopsis taxiformis
Color Present Red
Identification Long stem with smaller branches

The red sea plant has diploid life stages, which are so different that its form is named another species.

The red algae is very famous for its culinary uses; it is the most popular type of limu in the cuisine of Hawaii as a principal condiment. The name of the plant is also from the Hawaiian language, which means pleasing seaweed.

Essential oils like bromoform are also derived from this sea plant, which is found to have traces of iodine and many other organic compounds.

Scientists have discovered that feeding ruminants these algae in their diet would reduce their methane emissions by nearly 99%.


5. Gracilaria tikvahiae

Scientific name Gracilaria tikvahiae
Color Present Dark green
Identification flattened, slender, and unevenly branched

The green sea plant can grow up to 15cm tall. The cultured algae is usually dark green to nearly black.

The green algae, which are commonly found on limestone and basal substrates, can be attached or unattached to rocks. They originate from the Caribbean and Florida and are found in high-energy intertidal habitats.

These plants have a high ecological impact. Being distributed throughout the world is often associated with eutrophic conditions. Because of their hardiness and greater adaptability, they have the potential to be invasive species on Hawaiian reefs.

They have the ability to store large amounts of dissolved nitrate and nitrite, which helps them grow in fluctuating nitrogen availability.


6. Bleachweed

Scientific name Prionitis lyallii
Color Present Red
Identification flattened and highly branched thallus

The red sea plant emits a bleach-like smell when squished, which keeps away the grazing animals. Its color can range from reddish brown to blackish, and the branch varies from small, narrow teeth to long, narrow, and pointed.

These sea plants are perennial species that grow on rocks from intertidal and tidepools. They occur along semi-protected shorelines, where wave action can bring more nutrients. They are widely found in northern Mexico.

This red sea plant is often confused with narrow iodine seaweed.


7. American Glasswort

Scientific name Salicornia virginica
Color Present Green
Identification Woody stem and spine-like leaves

The green sea plant grows in various zones of intertidal salt marshes and can be found in alkaline marshes. They almost occur everywhere in wetlands.

This is one of the Salicornia species that is being tested as a biofuel crop, as its seeds are composed of 32% oil and can also be irrigated with salt water.

The sea plant can grow up to 50 cm, and its stems are photosynthetic, which later turn reddish brown with age. They grow in saline areas in the United States, Europe, and Africa.

This plant is eaten and is also called a pickle plant for its consumability.


8. Sarcodiotheca gaudichaudii

Scientific name Sarcodiotheca gaudichaudii
Color Present Red
Identification Cylindrical thallus and fairly brittle branches

The red sea plant has its color varying from light pink to dark or reddish brown and to straw yellow when bleached in summer. They grow up to 400cm in height.

They grow on rock and other hard substrates, usually small stones and shells, in the lower intertidal on the west coast of North America and range from Alaska to California.

Red seaweeds are a rich source of unique bioactive compounds and secondary metabolites that are known to improve human and animal health. It is also known that they have antimicrobial properties against certain pathogens.


9. Japanese Wireweed

Scientific name Sargassum muticum
Color Present Yellow
Identification autotroph with aerial vesicles

This yellow sea plant can grow up to 10 meters in height. They grow on half-tide to infralittoral areas and are fixed to solid substrates like rocks, stones, or shells.

The yellow plant originated in Japan but is transported worldwide with Japanese oysters. They are found on a large variety of land, which shows that they have huge tolerance for their environment.

The yellow sea weed causes economic and ecological problems as it is invasive, and due to its large size, it screens within the water column, preventing the penetration of light. They also help as antifouling activities.


10. Padina sanctae-crucis

Scientific name Padina sanctae-crucis
Color Present Brown
Identification curled, fanlike branches from a single stalk

The brown sea plant grows on rocks and shell fragments in the shallow sublittoral, seagrass meadows, mangrove roots, and coral reefs on tidal flats.

They are found in most of the world’s tropical waters, like Florida, the Caribbean Sea, and Brazil.

The sea plant is used in food and is known to be rich in fatty acids, which are an excellent source of nutrients for mammals.


11. Red grape

Scientific Name Botryocladia occidentalis
Color present red
Identification small grape-like bladders

Commonly found in California. This sea plant does not require high lighting. It grows by attaching to either a rock or a shell and grows very quickly. If you are an aquarist, this sea plant is perfect.

The fractions from this sea plant were tested and used against SARS-CoV-2 and blood coagulation. Also, the polysaccharides found in the cell wall of this sea plant interact with the blood co-factors.


12. Brown seaweed

Scientific Name Sargassum hystrix
Color brown
Identification porcupine-like, spiny

This sea plant is processed seaweed which is popular and well-known in Indonesia. This marine species appears bristly and spiny. These sea plants are also found in the Bahamas, Caribbean, and South Florida.

They grow up to the size of 10 to 14 cm and are 10 to 100 mm long or deep. This sea plant is also known as White- vein Sargassum. These sea plants grow widely in tropical regions.


13. Sargassum

Scientific Name Sargassum platycarpum
Color brown
Identification Golden brown leaves which come from thick branches

This sea plant has gold-brown leaves that are from a series of thick main branches. These sea plants grow up to a height of 30 inches or even deeper. These sea plants grow in marine but are mostly found in shallow water.

Again, if you have an interest in marine aquariums, then this sea plant is perfect for you. But this sea plant requires bright lighting and optimum flow rates.

This brown sea plant develops a deep anchor that can overcome turbulent environments.


14. Spherical turtle shell

Scientific Name Bornetella sphaerica
Color green
Identification disc-shaped holdfast

This sea plant is found in Indonesia and the Indo-Pacific region. It ranges from Madagascar to Japan, the Philippines, Hawaii, and northern Australia. This sea plant has a diameter of about 5 to 10 mm.

There is a cylindrical stipe that is continuous with a central vein that goes along the thallus.

This green sea plant grows on reefs, rocks, and dead coral heads. It grows in marine areas at depths ranging from the low intertidal zone to about 200 feet.


15. Hen Pen

Scientific Name Bryopsis plumosa
Color green
Identification distichous branches

This green sea plant is found in the British Isles, Europe, the Mediterranean Sea, the Black Sea, France, North America, Australia, New Zealand, and Japan. This sea plant can be found in intertidal pools.

This sea plant is dioecious, which means that species have distinct unisexual individuals wherein the male plants turn a yellowish green, and the females turn dark green. These sea plants undergo dioecious reproduction, which is biparental reproduction.

The thallus of this sea plant is small, erect, and grows up to 10 cm long. It grows in two opposing rows.


16. Chaetomorpha

Scientific Name Chaetomorpha aerea
Color green
Identification fine needle-like thallus

This sea plant is found in Chile. These sea plants produce oxygen and are trophic guild, exploiting the food resources and using the same feeding methods.

This sea plant forms a multicellular tubular thallus composed of multinuclear cells that are created when nuclear division does not form cell walls (siphonocladous).

Also, this sea plant is a photoautotroph, which means it is capable of transforming light into chemical energy.


17. Neptune grass

Scientific Name Posidonia oceanica
Color green
Identification ribbon-like tuffs

This sea plant is a seagrass that is endemic to the Mediterranean Sea only. This seagrass forms large meadows in the ocean environment and is an important part of the ecosystem.

This seagrass has a very high carbon absorption capacity and absorbs 15 times more carbon dioxide than a similar-sized Amazon forest can. Isn’t it fascinating? This seagrass can be one of the parts of the solution to global warming.

This seagrass grows up to 1 cm thick both horizontally and vertically. Its roots have rhizomes and tapeform leaves.


18. Callithamnion

Scientific Name Callithamnion corymbosum
Color red
Identification free filaments

These sea plants are distributed throughout Europe, Norway, Australia, America, Canada, Sri Lanka, and South Africa. These sea plants are also known to have a cosmopolitan distribution, which survives over a large range worldwide.

There are short ultimate branches carrying hyaline hairs. This sea plant is a group of species that exploit the same food resources and use the same feeding methods.

One interesting fact is that this red sea plant produces oxygen and is capable of transforming light into chemical energy.


19. Ceramium

Scientific Name Ceramium shuttleworthianum
Color Red
Identification spiny appearance

This red sea plant commonly grows around 2–5 cm, mainly in the lower intertidal zone at wave-exposed sites. The branches are enrolled with apices. At the ends of the branches, triangular spines with a single developing apex are formed.

The spine and the branches hold the base for multicellularity and merge into cortical bands.

There are other Ceramium species of sea plants that the shape of the spines can identify.


20. Ascophyllum

Scientific Name Ascophyllum nodosum
Color green
Identification loose lying in a shallow lagoon

This sea plant is sheltered on the intertidal coast of Norway. This sea plant is an indigenous habitat in Norway; hence, it is especially known as a Norwegian sea plant or seaweed. The branch spread in dichotomous branching.

This sea plant is dioecious, which means that sex-specific characteristics are noticeable. This sea plant is used for economic purposes and is cultivated widely in Norway for seaweed meal.

One interesting fact about this sea plant is that it loses its epidermal layer as a defense mechanism against epiphytes.

In conclusion, we can see how these colorful sea plants contribute to the well-being of the ocean ecosystem. We have seen how these colorful sea plants can be bliss to our eyes. We have seen a variety of sea plants that can serve as one of the solutions to global warming and also for medical purposes.

However, a conscious awareness should be made to preserve the sea plants from threats and destruction.


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