On May 31, 2010, PedricksCorner from Freedom, CA (Zone 9b) wrote:
I have always suspected this clumsy beetle was eating the aphids in my fruit trees and according to a fellow member here at DavesGarden who assisted me in it's identification and Wikepedia, I was right. They are considered important and beneficial predators of aphids. They supplement their diets with nector and pollen, thus sometimes being minor pollinators. Their larvae eat grasshopper eggs, aphids, caterpillars, and other soft bodied insects. When I was able to rid my fruit trees of the aphids the ants had brought, these "Soldier Beetles" dissappeared.