The coxella weevil, Hadramphus spinipennis, is a large stout, knobbly-backed weevil that feeds on coxella, Aciphylla dieffenbachii. Because of its large size (20-25 mm in length) it cannot be confused with any other species of weevil or beetle occurring on the Chatham Islands. Both adults and larvae feed on coxella, and this is the only known food plant. Adults and larvae produce characteristic feeding damage on coxella. Recognition of the feeding damage is an important aid in location of beetle colonies. This feeding damage is divided into four main types.