Today’s National Geographic Photo of the Day shows a butterfly with windowpane wings (also available as desktop wallpaper). The wings are mostly transparent with only two dots on each side.
There are other butterflies with transparent wings, for example this clearwing butterfly, the Greta oto (see images one, two, three, four), another the red clear-wing butterfly, and clear-wing moths like the Melittia calabasa or the Snowberry Clearwing Moth.