Beetle collection. Display of various weevil beetles (order Coleoptera) mounted and pinned on card. It is etimated that there are between 5 and 8 million species of beetle worldwide. All insects have six legs (three pairs), antennae and a segmented body (head, thorax and abdomen). Beetles, however have a hard carapace over their abdomen that supports and protects their bodies. They also have hard forewings. The study of insects is called entomology.