Giant spiders have been spotted in swarms on the ocean floor near Antarctica.

Researchers exploring the depths of the ocean have captured stunning footage of a spider the size of a dinner plate wandering along the seafloor near the South Sandwich Islands—a chain of volcanic islands close to Antarctica, in one of the most remote areas of the world. The spider was filmed at a depth of 2,104 meters. These marine creatures, known as pycnogonids, are distant relatives of land spiders, as reported by Live Science. However, unlike their terrestrial cousins, these enormous sea spiders boast a leg span of up to 51 centimeters.

According to the Schmidt Ocean Institute, the massive size of these spiders is a result of deep-sea gigantism—a phenomenon where deep-sea creatures grow significantly larger than their shallow-water counterparts. “The immense pressure and low temperatures, which pose insurmountable challenges for land dwellers like humans, allow some animals to have a very slow metabolism and achieve gigantic sizes,” the researchers noted in a Facebook post.

https://www.facebook.com/SchmidtOcean/videos/2128153254316284

Large animals are also capable of moving faster and covering greater distances in search of food or mates, which is crucial when both are in short supply. Deep-sea gigantism is particularly common near the poles, where cooler temperatures contribute to slower metabolic rates. Experts report that science has identified around 1,500 species of sea spiders, but likely many more remain undiscovered. Sea spiders inhabit oceans worldwide and range in size from just a few millimeters to the diameter of a large plate.

According to the Monterey Bay Aquarium Research Institute, the largest representatives of this group are typically found at depths between 2,200 and 4,000 meters. Instead of spinning webs or digging burrows like their land-based relatives, sea spiders utilize a specialized tubular mouth structure—a proboscis—to consume prey such as sea anemones and jellyfish. The footage of these deep-sea spiders was captured by remotely operated vehicle pilots during an expedition to the South Sandwich Islands. The research mission aimed to discover and describe new species inhabiting these frigid waters.