The oceans are home to several million species of astonishing sea creatures. Considering this enormous biodiversity, it comes as no surprise that these sea residents come in all possible shapes, colors, and sizes. Some of them, such as these terrifying deep sea creatures, look scary and nasty, but others might be breathtakingly beautiful. In today’s post, we will show you the latter as we take a closer look at some of the most spectacular marine animals. From anemones and sea spiders to coral fish and sea stars, these are 25 Most Astonishing Sea Creatures.
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Found in tropical waters of the western Pacific, the mandarin fish is a small, up to 6 cm (2.4 in) long coral fish famous for its unusual shape and beautiful, intense coloration.
Native to various locations within subtropical waters, the tube anemone comes in many different fluorescent hues and combinations of colors, which makes it a popular aquarium pet.
Flamingo Tongue Snail
Common on many Caribbean and Atlantic coral reefs, the flamingo tongue snail is a strikingly colored mollusk that feeds on toxic sea fans. It incorporates the fans’ venom and becomes toxic itself.
One of over 70 species of surgeonfish, the blue tang lives in coastal waters, coral reefs and inshore rocky or grassy areas in waters from New York to Brazil and as far east as the remote Ascension Island. It is famous for the sharp spines on its tail, which are said to resemble surgeon’s scalpels.
Found in warm waters of the Indian and Pacific Oceans, the mantis shrimp is one of the most captivating and colorful creatures in the sea. These beautiful crustaceans have the most complex eyes in the animal kingdom, containing millions of light-sensitive cells.
Native to the Western Atlantic Ocean as well as the Gulf of Mexico and the Caribbean, the French angelfish is an amazing tropical fish with dark coloration complemented by yellow stripes.
Leafy Sea Dragon
Found in the tropical waters around Australia, the leafy sea dragon is one of the most unusual and fascinating sea creatures. Reaching up to 20 cm (8 in) in length, it is a unique species of the seahorse.
Not related to the land spiders, the sea spiders are much simpler in form and function but are almost as common as their dry namesakes. These tiny marine arthropods can be found in most parts of the world.
Flower Hat Jelly
Although the flower hat jelly looks like a jellyfish, it actually belongs in the class Hydrozoa, while true jellyfish belong in class Scyphozoa. The flower hat jelly occurs in the West Pacific off southern Japan, and it delivers a painful sting.
Also known as the Brachyura crab or the swimmer crab, the harlequin crab is a stunningly colored true crab that occurs with sea anemones and tube anemones, close to shorelines of coral and rocky reefs.
Banggai Cardinal Fish
The Banggai Cardinal Fish is a remarkable tropical fish with silver coloration and vertical black stripes. An endangered species, it is only found in a rather small area around the Banggai Island in Indonesia.
Spotted Eagle Ray
Reaching widths of over 3 m (almost 11 ft), the spotted eagle ray is one of the largest eagle rays, with only the mantas growing bigger. It is an active swimmer and predator known to eat invertebrates and small fish.
Bright orange with 3 distinctive white bars, clown anemonefish are among the most recognizable and popular of all reef-dwellers. They reach about 11 cm (4.3 in) in length and are named for the multicolored sea anemone in which they make their homes.
A popular aquarium pet, the harlequin shrimp is a beautifully colored shrimp found in the tropical waters of the Indian and Pacific Ocean. It has a white body with large light blue spots. The males are slightly smaller than the females.
Also known as the blue glaucus and the blue sea slug, the blue dragon is a species of small, blue sea slug. Measuring just up to 3 cm (1.2 in) in length, this curious animal occurs throughout the world’s oceans, in temperate and tropical waters.
Native to the Amazon river basin in South America, the discus fish is one of the world’s most beautiful tropical fish. Due to its distinctive shape and striking coloration, the discus is a popular aquarium pet; it is sometimes even referred to as the “king of the aquarium.”
Venus Flytrap Sea Anemone
Named after its plant namesake because of its physical and feeding mechanism similarities, the Venus flytrap sea anemone is a large, deep-sea anemone that feeds by trapping food in its “mouth” structure as its prey enters the trap.
One of the most remarkable starfish, the royal starfish is a sea star that lives most commonly at the mid continental shelf around 20–30 m (70–100 ft) in the Western Atlantic. It is a carnivore and feeds on mollusks, which it catches with its arms and then takes to the mouth. Photo used with permission: Julie Worthy Photography (facebook)
Berghia Coerulescens is a species of sea slug that can be found in the Central and Western Mediterranean and the Northern Atlantic Ocean. This stunningly colorful creature reaches up to 7 cm (2.8 in) in length.
One of the most iconic tropical fish, the Red Lionfish is native to the reefs and rocky crevices of the Indo-Pacific, although it has found its way to warm ocean habitats worldwide. They are popular in some parts of the world as food but are far more prized in the aquarium trade.
Endemic to the Mediterranean Sea and parts of the North Atlantic, the short-snouted seahorse is a mid-sized, up to 13 cm (5.1 in) tall seahorse that inhabits shallow muddy waters, estuaries or seagrass beds.
Also known as the blackbar triggerfish or the Picasso triggerfish, the lagoon triggerfish is a remarkable tropical fish found on reefs in the Indo-Pacific region. It often occurs in Hawaii where it is called “humuhumunukunukuapuaa.”
Green Sea Turtle
Inhabiting tropical and subtropical coastal waters around the world, the green turtle is a large, weighty sea turtle with a wide, smooth carapace. Weighing up to 320 kg (over 700 lb), the green turtle is among the largest sea turtles in the world.
A species of sea slug, Phyllidia Babai is a colorful marine nudibranch that has been reported from several locations in the Pacific Ocean such Papua New Guinea, South Korea, and Australia.
The crown-of-thorns starfish is a coral-eating starfish native to the Indo-Pacific region. Despite its beautiful appearance, this species is often considered a pest as outbreaks of this creature pose significant threats to coral reefs, particularly the Great Barrier Reef.
Photo: 25. I, Luc Viatour, Synchiropus splendidus 2 Luc Viatour, CC BY-SA 3.0, 24. Bernard Dupont via flickr, CC BY-SA 2.0, 23. Laszlo Ilyes via flickr, CC BY 2.0, 22. Tewy, Blue tang (Paracanthurus hepatus) 02, CC BY-SA 3.0, 21. prilfish via flickr, CC BY 2.0, 20. Brain Gratwicke via flickr, CC BY 2.0, 19. lecates via flickr, CC BY-SA 2.0, 18. Sylke Rohrlach via flickr, CC BY-SA 2.0, 17. Chris Favero via flickr, CC BY-SA 2.0, 16. Bernard Dupont via flickr, CC BY-SA 2.0, 15 Bernard Dupont via flickr, CC BY-SA 2.0, 14. Brian Gratwicke via flickr, CC BY 2.0, 13. Ritiks, Clown fish in the Andaman Coral Reef, CC BY-SA 3.0, 12. Chad Ordelheide, Harlequin Shrimp 1, CC BY-SA 3.0, 11. Sylke Rohrlach via flickr, CC BY-SA 2.0, 10. Biotopica, criadero de peces disco, Biotópica, breeding discus fish Penang Eruption, CC BY-SA 4.0, 9. NOAA Photo Library via flickr, CC BY 2.0, 6. Alexander Vasenin, Common lionfish near Dunraven wreck, CC BY-SA 3.0, 5. © Hans Hillewaert, Hippocampus hippocampus (on Ascophyllum nodosum), CC BY-SA 4.0, 3. Brocken Inaglory, Total internal reflection of Chelonia mydas, CC BY-SA 4.0s, 2. Nhobgood Nick Hobgood, Phyllidia babai (Nudibranch), CC BY-SA 3.0, 1. Jon Hanson via flickr, CC BY-SA 2.0