Coleotichus blackburniae as they develop. This insect occurs on all the main islands of Hawaii. They are found on `a`ali`i ("Dodonaea viscosa") bushes and koa ("Acacia koa") trees. Also found on Formosan Koa (Acacia confusa) which is native to Southeast Asia. It has been commonly used in Hawaii as an ornamental landscape tree that has been deemed invasive. A. confusa and A. koa both have distinctive phyllodes that differentiate each species but since its introduction C. blackburniae has been recorded to associate with the invasive Formosan koa. Common to all true bugs, this species has no mouth parts with which to bite,
Acacia koa reaching in five years on a good site. Initially, bipinnately compound leaves with 12–24 pairs of leaflets grow on the koa plant, much like other members of the pea family. At about 6–9 months of age, however, thick sickle-shaped "leaves" that are not compound begin to grow. These are phyllodes, blades that develop as an expansion of the leaf petiole. The vertically flattened orientation of the phyllodes allows sunlight to pass to lower levels of the tree. True leaves are entirely replaced by long, wide phyllodes on an adult tree. Flowers of the koa tree are pale-yellow spherical racemes with