A mayfly swarm rises above a river in the last warm light of the day. Several nearby insects show translucent upright wings, slender pale bodies and long tail filaments. Farther away, the swarm becomes a loose cloud of tiny bright shapes scattered across the water. Different distances and directions give the movement depth.

Golden river light enters from a low opening between the wooded banks. A bright reflection stretches toward the foreground, breaking into short bars on the ripples. On the opposite side, dark trees provide a clear background for the nearest wings and tails. The insects remain part of a broad landscape, with the river bend and high foliage taking up much of the frame.

Small rocks line the shaded bank, and the surface carries muted reflections of the leaves above. A few insects soften with movement while the closest wing veins stay sharply visible. The warm sky, dark water and delicate forms create a quiet sense of activity. The whole scene captures the brief meeting of evening light, flowing water and a dense gathering just above the surface.