A bark beetle is the common name for the subfamily of beetles Scolytinae. Previously, this was considered a distinct family (Scolytidae), but is now understood to be a specialized clade of the "true weevil" family (Curculionidae). Although the term "bark beetle" refers to the fact that many species feed in the inner bark (phloem) layer of trees, the subfamily also has many species with other lifestyles, including some that bore into wood, feed in fruit and seeds, or tunnel into herbaceous plants. Well-known species are members of the type genus Scolytus, namely the European elm bark beetle S. multistriatus and the large elm bark beetle S. scolytus, which like the American elm bark beetle Hylurgopinus rufipes, transmit Dutch elm disease fungi (Ophiostoma). The mountain pine beetle Dendroctonus ponderosae, southern pine beetle Dendroctonus frontalis, and their near relatives are major pests of conifer forests in North America. A similarly aggressive species in Europe is the spruce ips Ips typographus. A tiny bark beetle, the coffee berry borer, Hypothenemus hampei is a major pest on coffee plantations around the world.
Bark beetle
Mountain pine beetles killed these lodgepole pine trees in Prince George, British Columbia.
Effects of bark beetle in the Bavarian Forest
Bark beetle gallery engraving the sapwood
Weevils are beetles belonging to the superfamily Curculionoidea, known for their elongated snouts. They are usually small – less than 6 mm in length – and herbivorous. Approximately 97,000 species of weevils are known. They belong to several families, with most of them in the family Curculionidae. It also includes bark beetles, which while morphologically dissimilar to other weevils in lacking the distinctive snout, is a subfamily of Curculionidae. Some other beetles, although not closely related, bear the name "weevil", such as the biscuit weevil, which belongs to the family Ptinidae.
Weevil
Curculio nucum