Many species are now extinct or have not been seen in decades. These include "C. arborea", "C. comata", and "C. pohaku", a cluster of species that formerly inhabited the drier, mesic areas of leeward East Maui where almost no native habitat remains. Because they are particularly sensitive to disturbance by pigs, "Cyanea" are often the first plants to disappear, even when the forest as a whole appears relatively healthy. Extinct species tended to have longer, more highly specialized flowers and to have narrower elevational and geographic ranges than the species that survived (Givnish et al. 1995).