Hibiscadelphus giffardianus viscosa"), and naio ("Myoporum sandwicense"). "H. giffardianus" is a small tree, reaching a height of and trunk diameter of . Hibiscadelphus giffardianus Hibiscadelphus giffardianus (Kilauea hau kuahiwi) is a species of flowering plant in the mallow family, Malvaceae, that is endemic to the Big Island of Hawaii. It is believed to be extinct in the wild; any remaining plants are threatened by habitat loss. Cultivated plants exist in Hawaii Volcanoes National Park. It inhabits mixed mesic forests on the slopes of Mauna Loa at elevations of . Associated plants include ōhia lehua ("Metrosideros polymorpha"), koa ("Acacia koa"), mānele ("Sapindus saponaria"),
Acacia koa survives best in pasture when planted under koa. This is because koa trees reduce radiative cooling, preventing frost damage to ōhia lehua seedlings. Koa is the preferred host plant for the caterpillars of the green Hawaiian blue ("Udara blackburni"), which eat the flowers and fruits. Adults drink nectar from the flowers. Koa sap is eaten by the adult Kamehameha butterfly ("Vanessa tameamea"). The koa bug ("Coleotichus blackburniae") uses its rostrum to suck the contents out of koa seeds. Koa is vulnerable to infection by koa wilt. Acacia koa Acacia koa is a species of flowering tree in the pea family,