Hibiscadelphus distans

Hibiscadelphus distans (Kauai hau kuahiwi) is an extremely rare species of flowering plant in the mallow family, Malvaceae, that is endemic to the island of Kauaʻi in Hawaii. It is known as hau kuahiwi in Hawaiian, which means "upland Hibiscus tiliaceus." It is a bush or small tree with heart-shaped leaves and yellow flowers and grows at between 1,000 and 1,800 feet (300 and 550 m) in the remnants of native dry forests. Despite its rarity, it is believed to be the only surviving species in the genus Hibiscadelphus which is only known from Hawaii, the other five species having recently become extinct in the wild, some being known from only a single plant....read more on Wikipedia.