How do water striders use their middle and hind legs while moving across water?

Water striders, which belong to the insect order Heteroptera, utilize their specialized middle and hind legs to navigate the surface of ponds and streams.

The middle pair of legs is primarily responsible for propulsion, allowing the insect to skate or run across the water. The hind pair of legs functions as a rudder, which the insect uses for steering. These long legs, which can sometimes reach more than twice the length of the body, are equipped with fine, water-resistant hairs on the feet (tarsi) that provide the necessary surface tension to keep the insect afloat.1

While the family Gerridae uses this specific division of labor for movement, other related insects like those in the family Veliidae may exhibit different adaptations; for instance, some species in the genus Rhagovelia use a fan-shaped arrangement of bristles on their middle legs to run against rapid currents.2