Scotorythra paludicola, koa moth. Humuula Trail. This native moth occasionally has outbreaks that defoliate koa trees over huge areas. One of these is currently going on across the eastern slope of Mauna Kea. When these pictures were taken, the current generation of adults was nearing the end of their lives. Hundreds of dead moths were scattered over the ground, and most of the living ones were rather dull-colored due to age.