Pacific-northwest-native
Guides
Laricobius nigrinus
hemlock woolly adelgid predator beetle
Laricobius nigrinus is a small predatory beetle in the family Derodontidae, native to western North America. First described by Kenneth Fender in 1945 from Oregon specimens, it is specialized to feed on adelgids, particularly the hemlock woolly adelgid (Adelges tsugae). Since 2003, it has been released as a biological control agent in the eastern United States to combat invasive adelgid populations threatening eastern and Carolina hemlock trees. The species exhibits a univoltine life cycle with aestival diapause and has established populations across multiple eastern states.