Megaplatypus mutatus males initiate galleries in healthy trees and call in females using pheromones. Both adults and larvae extend the tunnels, which eventually weaken the tree, lead to stem or branch breakage, and often tree death. Their ability to increase populations rapidly is impressive—in some cases, nearly 1,000 progeny have come from a single mated pair! This species has a broad host range, infesting both hardwoods and conifers. (Illustration by Pablo Nakamurakare and Esteban Ceriani-Nakamurakare, Ph.D.)