Animals Wildlife 19 Bizarre and Beautiful Starfish Species By Jaymi Heimbuch Writer California Polytechnic State University, San Luis Obispo Jaymi Heimbuch is a writer and photographer specializing in wildlife conservation. She is the author of The Ethiopian Wolf: Hope at the Edge of Extinction. our editorial process Twitter Twitter Jaymi Heimbuch Updated May 09, 2020 A diver hovers above a rocky reef where a sea star clings just off Cocos Island, Costa Rica. Ethan Daniels/Shutterstock Share Twitter Pinterest Email Animals Wildlife Pets Animal Rights Endangered Species Starfish, or more technically accurate, sea stars, are fascinating creatures and amazingly diverse. Most commonly thought of as a five-armed intertidal species, starfish come in myriad shapes, sizes, colors, arm counts, and are found from shorelines to the deep sea. And while they seem like docile creatures, they can actually be voracious and rather savage predators. Here are some of the many beautiful, odd and surprising species of sea stars around the world. Ed Bierman [CC BY 2.0]/Flickr Leather Star (Dermasterias imbricata) Found along the West Coast of North America, from Alaska to Mexico, the leather star lives in the intertidal zone down to depths of about 300 feet where it dines on everything from algae to sponges to sea cucumbers. Meanwhile, it does its best to avoid the morning sun star, another species of sea star that makes a quick meal (well, relatively speaking) of the leather star. Leather stars make up to 50% of the diet of the morning sun star. *** NatureDiver/Shutterstock Morning Sun Star (Solaster dawsoni) And here is that voracious predator. With anywhere from eight to 16 arms and usually red or orange coloring, the morning sun star looks, well, like a cartoon sun. It is found in the northern Pacific, from Japan to Siberia and down the coast of North America to California. Other sea stars literally run away from it if they're touched by it. Some, however, fight back, including the velcro star and rainbow star, which can pinch the morning sun star to make it recoil and provide a window for escape. Others have defense mechanisms — the slime star inflates itself and exudes a noxious mucus, and the sunflower sea star can detach an arm to get away. If a morning sun star can't catch a star of a different species, it has no problem chowing down on an individual of its own species. *** Ethan Daniels/Shutterstock Sunflower Star (Pycnopodia helianthoides) The sunflower star is the largest sea star in the world, reaching an armspan of 3.3 feet. That space is taken up by 16-24 arms. They're found along the coast of North America, from Alaska to California, but they're largest in the northern areas. They dine on sea urchins, clams and snails and are usually found in subtidal areas where there is always water, since they can't support their bodies out of water. *** jkirkhart35 [CC BY 2.0]/Wikipedia Pink Short Spined Star (Pisaster brevispinus) Even starfish look pretty in pink. This sea star can reach a whopping two feet in diameter, and can weigh up to two pounds. It dines on clams and sand dollars, so is usually found on sand or mud, but its soft texture allows it to also grip on coral and rocks where it can feast on mussels, tube worms and barnacles. This is also a celebrity species: Spongebob Squarepants' neighbor Patrick Star is a pink starfish. So next time you see one, ask for an autograph. *** Ethan Daniels/Shutterstock Granulated Sea Star (Choriaster granulatus) This species goes by many names, including the cushion sea star or doughboy star, for obvious reasons. The plump starfish is found in shallow waters on coral reefs and rubble slopes where it feeds on algae, coral polyps, and scavenges on dead animals. *** TheMargue [CC BY 2.0]/Wikipedia Royal Starfish (Astropecten articulatus) This vividly colored species is found along the east coast of North America, primarily in the southeast. While it can live at depths of up to 700 feet, it mostly hangs out at around 70-100 feet deep where it dines on mollusks. Unlike many other species of starfish, the royal starfish eats its prey whole. *** stevehullphotography/Shutterstock Bat Sea Star (Asterina miniata) This fascinating species is called the bat star because of the webbing between its arms, which (so some say) look like bat wings. It is found along the west coast of North America, from Alaska to Baja. While the species usually has five arms, it can have up to nine, and it can be a wide range of colors from green to orange to purple. So if you're wondering if you're looking at a bat sea star, check if it has the tell-tale webbing. *** Ethan Daniels/Shutterstock Crown-Of-Thorns Starfish (Acanthaster planci) The name of this species is fairly clear. The spines covering its upper surface make it look like, well, you know. Those spines are also venomous, which aid it in its quest for world domination. Found over a wide range in subtropical waters, from the Red Sea to across the Indian Ocean, and across the Pacific Ocean to the western coast of Central America, this species preys on coral polyps. As one of the largest starfish in the world, it has a voracious appetitive. When numbers are low, crown-of-thorns starfish help boost the biodiversity of coral reefs by preying on the fastest growing coral species. But if their populations become too high, they can wreak havoc on coral reefs. Their population booms are due in part from human fishing of and collection of their natural predators, the humphead wrasse and triton snail. *** Medtrails [public domain]/Wikipedia Pacific Blood Star (Henricia leviuscula) Despite the creepy name, this common starfish is actually a very small, slender species that feeds on sponges and bacteria. Meanwhile, its main predators are birds and humans. They are among the most brightly colored sea star species in the intertidal zone and are found at depths of over 1,000 feet. *** Alexander Vasenin [CC BY-SA 3.0]/Wikipedia Egyptian Sea Star (Gomophia egyptiaca) Found along the coasts of eastern Africa and Madagascar, this spiky sea star stays at depths of around 20-25 feet. Like may starfish, it can regenerate parts of its body that are damaged. But with those spikes, it doesn't look like a sea star you want to reach out and mess with. *** Andrea Westmoreland [CC BY-SA 2.0]/Wikipedia Nine-Armed Sea Star (Luidia senegalensis) It may not be the only sea star to have nine arms, but it's the only species to be named for the fact that it has nine arms. Found in the western Atlantic Ocean, this starfish, like many species, everts its stomach to engulf its prey, and essentially "swallows" with its stomach. The nine-arm sea star dines on mollusks, small crustaceans, and sea worms, as well as filters stomachfuls of sediment to feast on tiny organisms. *** NOAA [CC BY 2.0]/Flickr Brisingid Sea Star Skipping a specific species, these sea stars are so cool, we're highlighting the entire order! The 70 or so species within this order live in the deep sea, at depths between 330 feet to over 19,000 feet below. They are suspension feeders, using their arms, which number from six to 16, to filter water and capture food as it drifts by. They look almost more like a seaweed or coral than a sea star. *** Hectonichus [CC BY-SA 3.0]/Wikipedia Necklace Starfish (Fromia monilis) This jewel-like starfish is found in the Indian Ocean and western Pacific Ocean. Found in shallow water in rocky areas, it feeds on sponges and small invertebrates. It can get as large as 12 inches across, and has unusual and beguiling coloring. That plus its relative hardiness makes it a favorite for people who keep salt water aquariums. It is also called the red tile starfish for obvious reasons. *** Ed Bierman [CC BY 2.0]/Flickr Giant Spined Star (Pisaster giganteus) This bedazzled sea star is found on the western coast of North America, from southern California up to British Columbia. Found in rocky areas along the low tide mark, they feast on mollusks. This species can grow as huge as two feet in diameter, hence the name that includes "giganteus". Though they have few predators, they are prey items for sea otters and birds. *** Ethan Daniels/Shutterstock Pincushion Starfish (Culcita novaeguineae) Found in tropical waters of the Indo-Pacific, this unusual species of starfish creates its own little habitat by providing shelter for small shrimp that hide under it, and copepods that live on its outside. Even a species of fish, the star pearlfish, may make itself at home inside the body cavity of the pincushion star, emerging to feed. It would be hard to guess by glancing at it that it is a starfish at all, and not a type of coral! *** Ethan Daniels/Shutterstock Chocolate Chip Sea Star (Protoreaster nodosus) Mmmmm, chocolate chip cookies! Well, while this looks like a chocolate chip-studded starfish, it wouldn't exactly taste great. The dark nubs are a way for it to look more dangerous, and it works as it has few predators. Because of this, the sea stars actually provide a home on its surface for other species such as shrimp, tiny brittle stars, and juvenile filefish. Though it has few oceanic predators, it does have one serious predator -- humans. This species is collected as a tourist trinket and for the aquarium trade and are being overharvested in some areas. *** Ethan Daniels/Shutterstock Blue Sea Star (Linckia laevigata) This gorgeous blue sea star is found in the tropical waters of the Indian and Pacific Oceans, usually in shallow and sunny parts of reefs and reef fringes. It is a scavenger, and so acts as the clean up crew by feeding on dead animals. Like the chocolate chip sea star, the blue sea star has been part of the sea-shell trade for a long time, its skeleton sold as decoration. Because of this, the populations in some regions have seen dramatic decline. *** Dusan Wolczko/Shutterstock Australian Southern Sand Star (Luidia australiae) The mottled coloring of this species helps tp camouflage it in the sediment of seagrass beds of the Pacific Ocean around Australia and New Zealand. Typically sporting seven arms, it grows to be around 16 inches in diameter. It is sometimes found washed up on the beach after storms. *** Laszlo Ilyes [CC BY 2.0]/Flickr Panamic Cushion Star (Pentaceraster cumingi) Talk about gorgeous. This beautiful species is found around the Gulf of Panama and the Pearl Islands, all the way up to the northern parts of the Pacific Ocean. Appropriately, it is also called a knobby star. They can reach up to 18 inches in diameter, and feast on mussels and barnacles. They are considered a keystone species in tidepools thanks to the work they do to keep mussel populations under control. But it's not without effort -- it can take a starfish upwards of six hours to eat a single mussel.