striders

Striders is a common name for surface-dwelling insects that move on water or land, most notably water striders in the family Gerridae, order Hemiptera. They are semiaquatic predators that skim across the surface of ponds, lakes, and streams.

They have long legs, with the middle legs used for propulsion and the hind legs for steering. Their legs are covered with hydrophobic hairs that trap air, increasing buoyancy and enabling support on the water surface through surface tension. Their body design minimizes sinking while allowing rapid, agile movement.

Water striders occupy a wide range of freshwater habitats worldwide. They feed on small invertebrates that come to the surface, such as insect larvae and nematodes. Prey detection relies on sensing water surface vibrations caused by ripples and occasional visual cues. Predators include birds and fish, and some species use substrate-borne signals for communication.

Like other Hemiptera, water striders undergo incomplete metamorphosis. Females lay eggs on aquatic vegetation or other submerged substrates. Eggs hatch into nymphs that resemble smaller adults and molt through several instars before reaching maturity.

The Gerridae family comprises hundreds of species across multiple genera, varying in size from a few millimeters to nearly a centimeter. Water striders are studied for insights into biomechanics, surface-tension locomotion, and bioinspired robotics, and they can serve as indicators of water quality, since their abundance and distribution respond to habitat conditions.

In popular culture, the term Strider is used for various fictional characters or creatures, but this article concentrates on the biological group.