Water strider!!
They are covered in billions of tiny hairs that trap air around them, so they are quite water proof, can walk/run on water, will float back to the surface if submerged, and while under water, they can breath the air trapped in air bubbles around the hairs! They also have preapical Claws like mantises and they can adapt to have wings or no wings every generation, depending on whether the environment they are born into is better suited for wings or not!
They can also use ripples on the surface of the water like a radar system!