About 400,000 species of beetles have been described worldwide, with 30,000 occurring in Australia. However, out of this number, only 20,000 are scientifically described.
This is the largest insect order, representing approximately 40% of described insect species. It also contains some of the largest insects known. The group’s success and diversity is most evident in the vast range of habitats they exploited.
Appearance
Adults have a compact body with hardened forewings called elytra. Though not ideal for flight, these wings lift to allow membranous hindwings for flying. They feature variable compound eyes, diverse antennae, heavily sclerotized legs, and mandibulate mouthparts. Weevils stand out with their long slender snout containing their mandibular mouthparts.
Biology and Behaviour
Certain beetle species share similar habitats and diets for both adults and larvae. beetles , comprising a third of all animal species, exhibit various roles such as plant feeders, predators, parasites, or scavengers. While mostly terrestrial, some are aquatic, thriving in diverse environments like under bark, caves, mud, freshwater, dung, carrion, and more.
Reproduction is sexual, with females laying eggs near the food source. The larval stage feeds, moults, and pupates in a protective cell within or near the feeding medium.
Pest Status
Given the size and diversity of this group, it’s not surprising that many beetle species concern humans. Although not disease carriers, their insatiable feeding habits, especially the larval stage, often damage materials important to humans, including plants for food or timber, as well as stored items like seeds, food, clothing, leather, hides, tobacco, drugs, timber, and more.