Scotorythra paludicola Scotorythra paludicola Scotorythra paludicola, the koa looper moth, is a moth of the family Geometridae. It was first described by Arthur Gardiner Butler in 1879. It is endemic to the Hawaiian islands of Kauai, Oahu, Maui and Hawaii. The larvae mainly feed on "Acacia koa", but have also been recorded from "Falcataria moluccana", "Grevillea" and "Tristania" species. On occasion, this species develops enormous populations and defoliates entire areas with koa trees. During a recent outbreak of "S. paludicola" in 2013 on Hawaii Island, larvae were found to feed on isolated populations of the invasive tree "Falcataria moluccana" near Akaka Falls
Hakalau Forest National Wildlife Refuge numerous deep gulches. Rainfall decreases to about at elevations above , where majestic koa ("Acacia koa") and red-blossomed ōhia lehua ("Metrosideros polymorpha") trees form a closed-canopy forest. Further upslope, above , rainfall decreases to or less and native forest merges into abandoned pastureland where alien grasses and weeds, introduced as forage for cattle, are the dominant vegetation. Since 1989, over 400,000 koa, ōhia, and other native plants have been planted in this area as part of the refuge's reforestation program. The Pua Akala Cabin, located within the refuge, was nominated to the National Register of Historic Places in August 2008.