5 Weirdest Antarctic Species

Hoff crabs, springtails, and sea spiders are among the notable denizens of the southernmost continent.

In one of the most extreme places on Earth, you’re guaranteed to get some extreme life-forms—and Antarctica delivers.

From animals with built-in antifreeze to a hairy-chested crab, the coldest continent is chock-full of odd creatures. I recently asked Huw Griffiths, a marine biogeographer at the British Antarctic Survey, for his list of the five weirdest Antarctic species.

Hoff Crab

First up: The “Hoff” crab, a yet-to-be-named species whose nickname honors bare-chested Baywatch actor David Hasselhoff. Recently discovered on a hydrothermal vent system in Antarctica, the hoff crab—a type of “yeti” crab—farms bacteria on its furry chest as its main source of food.

The creature also “lives in a very hot place [in what’s] a normally cold environment,” Griffiths said. Swarming around steamy vents 1.5 miles (2.5 kilometers) deep, the crabs could represent the densest population of animals ever found, he added.

Icefish

Antarctica is also home to icefish, a type of see-through fish with glycoproteins instead of red blood cells. These proteins attach to small ice crystals in the fish’s body and work as an antifreeze, enabling it to live in freezing water.

“Icefish are from a group of fish spread out to fill a lot of the niches that would be filled by other types of fish in the rest of the world,” Griffiths said. (See Antarctic-animal pictures.)

Springtail

Another Antarctic critter blessed with antifreeze is the Antarctic springtail. Though only one to two millimeters long, the springtail is the continent’s biggest land animal: “It’s a giant in its environment,” he said. (Seagoing animals such as seals and penguins are not considered land animals.)

What’s more, “these tiny animals can survive being frozen solid and defrosted on a regular basis,” Griffiths said. “Put them in a freezer, and they’ll happily walk around again.”

Sea Spider

Antarctica’s land animals may be teensy, but their sea creatures can get huge, thanks to the high amounts of oxygen in the water. Gillless creatures such as sea spiders breathe through holes in their bodies, which allows more oxygen to be absorbed into their bodies—thus allowing them to grow bigger over time.

These Sea Spiders 'Breathe' Through Their Legs

For instance, in Europe, a sea spider “is the size of your little fingernail—and then you go to Antarctica and it’s the size of your dinner plate,” he said.

Sea spiders “are more common and have more species in Antarctica than anywhere else in the world,” he added.

Glass Sponge

Last but not least on Griffith’s list are glass sponges, which “get their name because their skeletons are made out of silica and come in a range of unusual shapes,” he said.

Though relatively uncommon in most of the world, they’re abundant in Antarctica, where they dominate the seafloor and provide habitat for hundreds of other species. A glass sponge is “kind of a living skyscraper for everything to grow on,” he said.

Scientists have to be careful handling the sponges, Griffiths noted, since their tiny, needle-like parts can get stuck in the skin.

Isopod

Finally, I’ll add my own favorite Antarctic creature to the mix: the isopod. I got to hold one of these squirmy crustaceans during a 2011 visit to McMurdo Station, the biggest U.S. research station in Antarctica. (Read posts from my fellowship to Antarctica.)

“Antarctica,” he said, “is one of those places where there are always surprises.”

Christine Dell’Amore is the author of South Pole, a book celebrating the 100th anniversary of Robert F. Scott’s expedition to the South Pole.