Spider Lives Its Whole Life Underwater
The water spider uses its swimming capacity to capture prey. Its web is used in other ways.
The water spider is the only spider that lives its entire life under water, although it needs to breathe just like other spiders. And instead of catching prey in a web, it uses its excellent swimming capacity to catch up on and kill its prey with poison. The web, which its spins between aquatic plants, is used to hide behind, when it is hunting.
The water spider’s life would be very troublesome, if it were to move to the surface to breathe all the time, but by means of the water-repellent hairs covering its abdomen, it can collect a layer of air at the surface and use it as an oxygen bottle. Moreover, it spins a web that it fills with air bubbles, moving into it like a diving bell.
The spider collects air with the hairs on its abdomen, creating a diving bell with its web.