Hibiscadelphus hualalaiensis (Hualalai hau kuahiwi) is a species of flowering plant in the mallow family, Malvaceae, that is endemic to the Big Island of Hawaii. The last known plant died in 1992, making it most likely extinct in the wild; any remaining plants are threatened by habitat loss. It inhabits dry and mixed mesic forests on the slopes of Hualālai at elevations of 915–1,020 m (3,002–3,346 ft). Associated plants include ʻōhiʻa lehua (Metrosideros polymorpha), lama (Diospyros sandwicensis), māmane (Sophora chrysophylla), naio (Myoporum sandwicense), ʻālaʻa (Pouteria sandwicensis), pāpala (Charpentiera spp.), ʻaiea (Nothocestrum spp.), poʻolā (Claoxylon sandwicense), and Kikuyu Grass (Pennisetum clandestinum). H. hualalaiensis is a small tree, reaching a height of 5–7 m (16–23 ft) an