Which group of beetles includes longhorn, roundhead, and flathead beetles?

The group of beetles that includes longhorn, roundhead, and flathead beetles is known as woodborers. This classification reflects their common habitat and feeding habits, as these beetles primarily infest and damage woody materials, including trees and wooden structures.

Woodborers are characterized by their ability to penetrate and utilize wood as both a food source and a site for their larvae to develop. Longhorn beetles, for instance, have long antennae and are notorious for their wood-boring behavior, while flathead and roundhead beetles also exhibit similar traits, targeting decaying and sound wood to lay their eggs.

This behavior can lead to significant structural damage if left untreated, making the identification of woodborers essential for effective pest management. The other choices, such as powderpost beetles, ants, and ambrosia beetles, represent different categories or groups with distinct characteristics and behaviors, focusing either on different forms of infestation or ecological roles that do not include the specific beetles mentioned in the question.