Hau Kuahiwi (Hibiscadelphus giffardianus) is a Hawaiian tree. The last wild one died in 1930. The reasons for its disappearance are not entirely understood, but it is clear that the destruction of natural plant life by cattle and clearings for farming played important roles. The disappearance of the Hibiscadelphus from the wild led to the disappearance of the Proterhinus weevil, discovered in 1917, which laid its eggs in the old limbs of this tree. Hibiscadelphus was saved by botanical gardens and was reintroduced. However, the weevil did not survive the disappearance of its host in the wild, and the species became extinct. Numerous other Hawaiian insect groups are also very specific to their plant hosts (long-horned beetles [Plagithmysus] and leaf bugs [Nesiomiris] among others): as the plants become rarer, the insects face the same fate as Proterhinus.
