Diving bell spiders of the species Argyroneta aquatica have the ability to swim, and they use this adaptation to live underwater. Although they live and swim in the water, diving bell spiders still breathe air by creating air pockets underwater that they use as homes.
Diving bell spiders get their name from the females' ability to spin an underwater web, known as a diving bell, that catches air. During the day, the spiders venture out to hunt and mate, and they return to the diving bell later to digest their prey and lay eggs. Males build smaller diving bells used solely for oxygen replenishment, since they don't need a place to lay eggs.