Cyanea angustifolia (Cham.) Hillebr.

Cyanea angustifolia (Cham.) Hillebr.. Cyanea angustifolia is a shrub in the genus Cyanea that is endemic to Hawaiʻi. In Hawaiʻi, it is referred to as ʻAku as well as Hāhā, which is the term for the generalized Cyanea genus. C. angustifolia was a food source during times of food scarcity for the Hawaiians. This shrub is characterized by specialized flower shapes and it is found at higher elevations in wet environments.