Raft spiders

Raft spiders use the water's surface in the way that other spiders use webs. Ripples made by insects on the water's surface are detected through the raft spider's front legs. The short, velvety, water-repelling hairs covering the body and legs then allow these large spiders to do the seemingly impossible - walk on water. They skate quickly across the surface and subdue their prey. Of the 100 or so species of raft spider, all but a very few are semi-aquatic, living in and around areas of permanent water such as marshes and ponds.

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