Water covers over 70 percent of Earth, with 96.5% of it in oceans. However, 80 percent of the ocean is remains undiscovered. While 91% of marine organisms are yet to be described, here are some animals found in the marine and freshwater ecosystems.
Anglerfish
Anglerfish are carnivorous fish, with most species living in the deep Atlantic and Antarctic oceans. Female anglerfish have a bit of dorsal spine with luminous flesh at the end that hangs above their mouths to bait prey. The male anglerfish is smaller than the female and does not have this rod. Instead, they fuse to female anglerfish, connecting to skin and bloodstream..
Axolotl
Axolotls are carnivorous amphibians that prefer to stay in the water. They are from Lake Xochimilco in Mexico. Axolotls have wrists and ankles made of cartilage and feathery gills at the sides of their heads to get oxygen. Like other salamanders, axolotls can regrow limbs. The population of the axolotl is in decline due to the pollution and the introduction of large fish to the lake.
Cuttlefish
Cuttlefish are carnivorous cephalopods that live in tropical or temperate waters near the coast. They are related to the octopus and the squid. Cuttlefish have eight arms and two long tentacles to capture prey. They also have an internal shell for buoyancy called a cuttlebone. Known for their ability to camouflage, cuttlefish can change both their colour and their texture thanks to specialized cells on their skin.
Bumphead Parrotfish
Also known as Green Humphead Parrotfish, Bumphead Parrotfish are the largest parrotfish and the largest reef fish. They have fused teeth, and they eat live corals and algae, consuming up to five tonnes of corral reef per year. After absorbing the nutrients, the inorganic material from the corral is excreted as sand. Bumphead Parrotfish can grow to be 1.5 m in length and weigh 75 kg. The population of the Bumphead Parrotfish is listed as vulnerable due to overfishing, habitat loss, and climate change.
Whale Shark
Whale sharks are the largest fish of the ocean, reportedly able to grow to 18 m in length. Most weight about 14 metric tons. They are carnivores, eating plankton by passively filtering water through their gill slits. Their small teeth are thought to be vestigial structures, not necessary for feeding. They have unique patterns of white spots on their backs in between pale stripes. Whale sharks are found in warm waters. They are categorized as endangered, with populations in decline.