Monochamus


Monochamus is a genus of longhorn beetles found throughout the world. They are commonly known as sawyer beetles or sawyers, as their larvae bore into dead or dying trees, especially conifers[1] such as pines. They are the type genus of the Monochamini, a tribe in the huge long-horned beetle subfamily Lamiinae, but typically included in the Lamiini today.

If sawyer beetles infect freshly cut pine logs, they can cause a 30–40% loss in value due to the tunnels their larvae bore. It is important to process logs within a few weeks of cutting or store them in water to minimize damage.[2] Some species are known to transport phoretic Bursaphelenchus nematodes, including B. xylophilus which causes pine wilt disease.[3]

The genus is very large, and its boundaries have varied considerably over time, with many species placed in this genus that have long since been removed, and species placed in other genera that have been added, and there are at least 20 subgenera presently recognized by most authorities.[4]


Notable sawyer (M. notatus)
Spotted pine sawyer (M. maculosus)