These are lookdowns. If you look at these fish from the front, they are so flat they almost disappear. From the side, they appear to be looking down their noses at something.

You often see them in aquariums where they school up in large numbers and make a beautiful show when they all turn together, flashing their sides then disappearing as the turn toward you.

I love the shape of these fish, especially the uppity attitude in their faces and their delicate, trailing fins.