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 confirmed this close relationship; the estimated time of divergence is about 1.4 million years ago. "A. heterophylla" sequences nest within those of the more diverse "A. koa", making the latter paraphyletic. Both species are thought to be descended from an ancestral species in Australia, presumably their sister species, "Acacia melanoxylon". Dispersals most likely occurred via seed-carrying by birds such as petrels. Both species have very similar ecological niches, which differ from that of "A. melanoxylon". A closely related species, koaia or koaie ("A. koaia"), is found in dry areas. It is most easily distinguished by having smaller seeds that are