Can You Identify All of These Creatures That Live in Coral Reefs?

By: Kennita Leon
Image: Shutterstock

About This Quiz

Coral reefs take millions of years to build, and if you have ever had the opportunity to swim, dive or snorkel in and around these magnificent reefs of color, you can imagine why. They are some of the most stunning scenery in the world, bursting with vibrant color, hidden in plain sight as they lie just below the waters of the world's oceans. Teeming with life, coral reefs are also the most diverse of all marine ecosystems; at least 25% of the ocean and sea life depends upon the reefs for food and shelter. 

This quiz is all about the creatures who live in and around the world's coral reefs. They provide the color, the beauty and sometimes the sustenance for the reefs to grow. But how many of these creatures can you identify from an image? They may look familiar, but are you able to name them? Could you tell if you are looking at a clownfish or is it a scorpion fish? Are you looking at a sea sponge or a sea urchin? 

This quiz will be a challenge, but will also be the most beautiful quiz you've taken in a long time. So, take a dive and see which of these wonderful creatures you can identify!

Sea sponges are scientifically known as Profiera, which means "pore-bearing." This refers to the numerous tiny holes that can be seen on the surface of this multicellular organism. These pores allow water to flow throughout this immobile creature, providing it with essential nutrients and allowing waste to be released.

This multicolored organism is often referred to as a sea slug, due to its physical similarity to the land animal. Nudibranchs are in fact mollusks which inhabit warm tropical climates. This oblong-shaped animal has horns and gills on its back but is also quite versatile.

Groupers are large sea predators identified by its domineering presence; it has a short, bulky frame and a large mouth. This ambush predator can be found lurking among coral reefs for squid, fishes and even small sharks that they attack and swallow whole. The largest grouper is the goliath grouper- a fierce predator that can weigh over 1,000 pounds and extend up to eight feet long.

The clownfish is a small fish of 2-5 inches long that can be found in a variety of colors, such as orange, black, yellow and blue. It enjoys a symbiotic relationship with the sea anemone. The clownfish is also a popular animal, that was made famous after its appearance as a main character in the Disney movies "Finding Nemo" and "Finding Dory."

The electric eel is an elongated carnivore that can be found in the South American waters of the Amazon and Orinoco rivers. Their main defense against predators is the thousands of cells found in their body that can generate 600 volts of electricity- powerful enough to kill a human. This compensates for their poor vision, and they use it to their advantage when navigating the murky waters for fish.

Parrotfishes are beautiful translucent marine animals that can weigh up to 100 pounds and grow over four feet in length. They can be found in about 80 species, but are known to be complex creatures that alternate their sex throughout their lifetime. Parrotfish feed on mostly on algae it finds among the tropical reef it inhabits.

Snapper is a long pinkish reddish saltwater fish that is a highly sought out by food lovers worldwide. Fortunately, female snappers produce over 200 fish in the months of May-October and begin to reproduce at two years old. Snappers are carnivores that use their large teeth to feed on fish and crustaceans they catch along the Gulf of Mexico and the Atlantic.

Jellyfish are invertebrates that have been in existence for millennia and are versatile in nature, with the ability to survive in a variety of temperatures and depths of water. The top part of their body is shaped like a bell and a mouth that acts as an orifice for food and waste. Perhaps their most notable feature is their tentacles, which can sting or paralyze their prey before it is consumed.

Corals are beautiful organisms made up of tiny polyps and a tough exterior called a cacile, which forms a tough protective base. Many corals have been growing for millions of years after a polyp has attached to a rock and multiped into numerous clones. As time goes by, the clones connect to form a colony and eventually coral reefs.

The scorpionfish is a dominant predatory marine animal that is frequently caught and kept in aquariums due to its physical appearance. Its entire body is scaly and covered in feather-like fins, making it very easy for this fish to camouflage. The scorpion fish is a nocturnal predator that hides in the fissures of corals even during the daylight before ambushing its prey.

This anemone is named after the anemone flower that grows wild in many nations of the world, such as Europe and North America. Anemones are the perfect example of beautiful but dangerous animals that use their poisonous tentacles to capture their prey. They are predators that attach themselves to rocks or coral reefs on the sea bottom and launch their tentacles at their prey when ready to feed.

Also known as starfish, sea stars are small organisms that look the same as the astronomical star. They are from the sea urchin family and do not have a brain or blood flowing through their bodies. They do, however, contain a nervous system made up primarily of water that filters nutrients throughout their bodies.

Crabs are members of the crustacean species- a group of animals such as lobsters and insects, with a hard outer skeleton and segmented limbs. Crabs are versatile animals that can live on water and on land and are also equipped with ten legs that they can regenerate after a year. They also have a sharp pair of claws by their heads which they use for defense and to capture their prey.

Sea snakes are part of the cobra family and can be found in the Pacific and Indian ocean. Although they live among coral reefs, they also live in swamps, mangroves and have been found in sand. As sea animals, they are excellent swimmers, and they look much like eels when traveling through water. Though their bodies have adapted to the sea world; they have lungs instead of gills and need to periodically surface for air.

Snails are creatures that are known for their slow movement but not much else. They are, however, interesting animals that have been at the center of scientific experiments, due to a mucus that they produce. Some research suggests that it may contain restorative powers, capable of healing wounds. Snails are from the gastropod family that slugs also belong to.

Octopus is a derived from the Greek language and refers to the eight tentacles of this animal. These tentacles are poisonous but are also dangerous for another reason: they enable the octopus to perform many tasks at once, such as searching for food while capturing an animal. Octopi also have large heads where all their vital organs are stored but have no protective shells. This works to their advantage, enabling them to easily hide and squeeze through crevices, either to evade predators or to ambush their prey.

Apart from being a delicious addition to a meal, this marine animal also contains an antioxidant named selenium, that is believed to reduce one's risk of developing cancer. Luckily, there are over 2,000 species of this animal that can be found in lakes and rivers and near the seabed.

Lobsters are marine animals that seem to have habits and bodily functions different from the rest. They taste food with their legs, use their stomachs to chew, and the female lobsters usually seek the male counterpart for reproduction. There are also two types of lobsters, clawed and spiny- the clawed are found in cold waters whereas the spiny lobsters live in warm waters. These complex organisms have ten legs as well as intestines, stomach, brain, heart and nervous system.

Turtles are some of the earliest reptiles to arrive on Mother Earth, millions of years ago, along with other primitive animals such as dinosaurs. Its skeletal shell protects its body much like how our skin protects us from harm. Some turtles are carnivores, while others are omnivores; generally, they eat grass, beetles, and fruit. As they mature, their diet becomes more plant-based.

Nautilus is a creature of the cephalopod family, characterized by its tube-like shell that can contain over 30 chambers. It is noted for its buoyancy, which is regulated by the siphuncle that pumps chlorine and ions into its chambers. Also, there are only six recognized species of this creature, which have maintained their characteristics throughout the years.

Clams are big mollusks with multi-colored mantles and a thick zigzag-shaped shell. They enjoy a symbiotic relationship with algae by providing it with protection and sunlight while feeding on the food the algae receives through photosynthesis. This contributes to the huge size of some clams, which can weigh up to 500 pounds.

This carnivorous animal of the tropical waters is at risk of becoming an endangered species due to overfishing. Angel sharks have a flat frame with fins that look much like wings, giving it the appearance of a large stingray. When it is not being captured by humans, this ambush predator just might be laying still in the sand before clamping down onto its prey with its powerful jaws and sharp teeth.

Conch are herbivores that feed on small seawater plants such as algae, but they have many predators such as turtles, crabs and sharks. They reproduce through copulation, and the pregnant female lays thousands of eggs and hides them in the sand, away from predators.

Scallops are small animals with no head, They are bivalve mollusks, which means that it has two valves/sides that are made up of shells that are flat and spread out, much like a fan. Its main defense against predators is its ability to swim by flapping its shells away from the threat. Many scallops are captured anyway and used in a variety of dishes.

The sea urchin, also known as sea hedgehog, is a small, round animal with numerous poisonous spikes jutting out of its body. Despite its appearance, this omnivore is preyed upon by other marine animals such as large fish and crabs. Aristotle's lantern is the name given to a sea urchin's mouth, that is used to shave food off of rocks or to even drill into sharp surfaces. Due to water pollution, sea urchins' survival is threatened.

This bottom-dwelling fish is a large predator with sharp teeth that poke out of its mouth, even when closed. Its fierce appearance belies its true personality; it is a non-threatening animal that only attacks when provoked. It usually feeds at night and surfaces to the ocean for air that it stores in its stomach. The sand tiger shark's tendency to frequent the shore gives it its unique name.

Oysters are small marine animals that are found in colonies in shallow waters. They have many fascinating characteristics, including their ability to change their gender and to produce pearls. They keep the ecosystem balanced by consuming sediment and algae that threaten other marine life. More so, oysters are harvested by humans for their ability to filter up to 50 gallons of water at one time, using their gills.

This echinoderm has a hairy exterior with numerous spines. It is also known as a serpent star, due to the quick movement of its body in the water with its five arms. It is more active at night, but lives on immobile organisms such as sponges. Brittle stars also have the ability to easily regenerate their limbs, which tend to break off easily during defense.

Squid is a part of the cephalopod family, similar to the octopus. This eight-armed creature has a siphon that helps it breathe, navigate through the water and to expel waste. This interesting animal has the ability to glow in the dark and even has three hearts! Squid use their many tentacles to capture their prey of fish and other squid; the only threat to their existence is the predator- the sperm whale.

The word "manta," which means blanket in Spanish, was used to name this giant ray because of its flat body. Manta rays have big brains and are smart animals that can even challenge the intelligence of dolphins. They do, however, have an odd habit of leaping out of the water, possibly to attract other mantas or dispose of waste. Manta rays are slow to reproduce but give birth to live pups every year.

Horseshoe crabs are not crabs but are actually chelicerates- relatives of the arachnid class that spiders belong to. They do have a hard exoskeleton shaped like a horseshoe, hence its name. Although they are like other anthropods, horseshoe crabs are Merostomata because their legs are attached to their mouths.

These creatures are small, but essential in preserving the marine ecosystems. They need carbon dioxide and sunlight to survive and ingest phytoplankton for food. Krill are plentiful in the oceans of the world, with 85 species and over 100 million in total. When they congregate, their swarm can be seen as far away as space. The survival of Antarctic krill is under threat due to global warming and the increasing unavailability of ice algae for food.

This type of shark has little distinctive features apart from a ridge along its back and its thicker body and rounder head, in comparison to the gray shark. These reef-dwelling sharks usually stay close to its environment and tend to live in isolated regions. They can produce 6-16 pups which stay within shallow waters to avoid predators while their parents are offshore. Galapagos sharks are found worldwide but mostly in tropical waters.

The surgeonfish is known by many names such as the Pacific blue tang and doctorfish, and it is frequently kept in aquariums by humans. This small fish was named in recognition of the small spines along the bottom of its body, which are shaped like a scalpel. One of these spines along its tail contains venom that serves as protection. Surgeonfish also help the ecosystem due to their tendency to consume algae from coral reefs. This helps to keep the coral healthy and free from suffocation.

The butterfly fish appears similar to the angelfish because of its bright colors, patterns, and shape. They have stripes of black around their eyes, which often confuse predators as to their next move. Their bright colors are also adaptable and tend to fade to blend into the color of the coral reefs they live . Butterfly fishes are persistent hunters that spend extended periods using their thin snouts to uncover worms and polyps hidden in the rocks and reefs.

This elongated animal is 3- 12 inches long, with a thick skin and tentacles around its mouth, that it uses to feed on algae and other small organisms. Sea cucumbers are not afraid to use their own bodies to scare off enemies. When threatened, they contract their muscles repeatedly until their internal organs are ejected out of their anus after the predator. Soon after, the lost organs are regenerated within their bodies.

Manatee, also known as sea cows, are large aquatic animals. They are slow and herbivorous - similar to terrestrial cows in this way. They are relatives of elephants and can be as long as 13 feet and can weigh 430 to over 1,000 pounds. Manatees are peaceful animals, skilled swimmers but are vulnerable to predators both human and animal, due to their slow movements. According to the National Geographic website, manatees are at risk of endangerment.

Sea turtles, also called marine turtles, are reptiles that can grow up to several feet in length and weigh over 1,000 pounds. Turtles are the travelers of the sea and can cruise over 9,000 miles a year. The females do appear to have a sentimental streak and return to their place of birth when it is time to lay their own eggs. Every 2-3 years, mothers can lay up to 150 eggs, but the young are left to hatch and survive on their own. As a result, thousands fall victim to predators and do not mature into adulthood.

This is a relative of the lionfish and also has characteristics of the scorpion fish. They are known to position their bodies strategically to gain a full view of their prey before pouncing on it like a hawk- hence their name. The spotted hawkfish can perch from its viewpoint safely because of its skinless pectoral fins that are not affected by the rough texture of the coral. The hawkfish is found in tropical climates and can be found in the Indo Pacific region.

This red- and white-striped fish has long feathery fins and a hostile personality. It is a fierce predator that can swallow its prey in only one bite and will eat members of its own species when food is scarce. This carnivore will eat crustaceans and fish and is preyed upon by humans and large fish such as eels.

Wrasses are marine fish of the Labridae family, many of which are brightly colored. They are among the most abundant reef fishes, with over 500 known species, ranging from 5 centimeters to 2 meters in size. Wrasses eat a variety of foods from algae to worms and small invertebrates, some species acting as cleaners by feeding off external parasites of other fish.

Triggerfish are brightly colored fish, typically marked with lines and spots, inhabiting tropical and sub-tropical waters, generally in coastal areas. They feed on crabs, shrimp, sea urchins and worms, sometimes via digging them out from the ocean bottoms by flapping their fins and squirting water from their mouths. Triggerfish are also notoriously known for being ill-tempered and aggressive.

Seahorses are tiny fish that gained their name from their horse-shaped head. There are over 40 species found in shallow tropical to temperate waters around the world and range from 13 millimeters to 35 centimeters in length. Their diet typically consists of plankton, small fish and small crustaceans. Instead of the female, male seahorses carry the embryos of their young.

Cuttlefish are marine animals belonging to the class Cephalopoda, which also include squid and octopuses. Despite their name, they are classified as mollusks. Found in warm, tropical, shallow waters to the depths of the deep oceans, cuttlefish are carnivorous and most commonly prey on small crustaceans such as shrimp and crabs, fish and even other cuttlefish. There are over 100 known species with sizes ranging from 6 inches to 20 inches.

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