Beetles are the most fantastically diverse group of insects on the planet. In addition, they are also the largest order of any animal in the entire animal kingdom. There are upwards of 300,000 species documented today and many many more expected to exist. The word Coleoptera itself comes from the Greek word meaning shield, and the root “ptera” meaning wing. The name “shield wing” refers to the fact that the fore wings in all beetles have been hardened over to form a structure called an elytrum. This acts as a protective cover for the delicate hind wings. These hind wings are so fragile because often times, in order to fit underneath the elytra, the wings must be folded in a really intricate way. Think about how a ladybug sits with its hardened fore wings up while it folds it paper thin hind wings into the space just above its abdomen after alighting on your finger. Because of this, although most beetles fly, they cannot fly particularly fast or long.
The role beetles play in the environment is a very important one. Some are predators, and prey on smaller insects and other animals, and therefor contribute to the food chain. Others are scavengers, and forage for food. Along with these there are many beetles that contribute to decomposition. Organisms such as the dung and carrion beetles are reasons why we are not wading through a sea of dead animal carcasses and fecal matter all day. Last of all, there are the parasitic beetles.
Many beetles, especially the larva, are detrimental to crops or plants that are important to humans. One species, the emerald ash borer, is a small green beetle very harmful to ash trees. The beetle is shown below.
This beetle bores through the outer layers of ash trees, which can be very harmful to the tree and its inhabitants. As an effort to combat this predator, scientists and engineers have teamed up with entomologists to create an emerald ash borer look alike, which will deliver a shock to kill any male that attempts to mate with it.
Pictured above are just a few of the many variations of beetle species. They come in so many different colors and shapes and sizes, sometimes it is hard to remember that they all belong to the same order of insects. One of my personal favorites is the goliath beetle, a large insect pictured in the bottom left. It has orange elytra and a striped thorax.
Like bees, wasps, ants, and their kin, mentioned in a previous post, and like butterflies and moths, beetles undergo complete metamorphosis. They start as eggs, and hatch into larvae which are more commonly known as grubs. They then pupate in a sessile stage, and then hatch from the pupa into a full adult. Some larval stages are aquatic, and some adult stages can also be aquatic. Predacious diving beetles, whirligig beetles, and water scavenger beetles all have aquatic adult forms with specially developed legs for swimming, diving, or paddling.
Beetles are one of the best insects to keep as pets. Species such as the blue death feigning beetles are particularly interesting to keep, because they are easy to care for, and when holding them they like to pretend that they are dead! They are very entertaining for children and adults alike. Another easy to keep as a pet beetle is a Bess beetle. They are large and black, with vertical ridges going down the thorax. Their elytra are fused, so they are not able to fly. This makes them good pets because it is difficult for them to escape.
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I always learn so much from these posts! (Probably because I have little to no knowledge coming in). It’s so cool how beetles have “shield wings” to protect their more delicate wings. I was also shocked to hear that they are largest order of any animal in the entire animal kingdom. That’s so crazy to me, I really never would have guessed that. But, once I put the more I thought into it really makes sense, and I just didn’t realized it because they’re so small and I come across them so infrequently.
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Since I know absolutely nothing about bugs I always learn so much from your posts! It is clear in your tone and word choice how knowledgable and passionate about this topic, it it great. I never knew so many different kinds of beetles existed, to be honest I always thought beetles were just beetles. It was cool to know each kind of beetle may search for food in different ways. Although I don’t think I would want an insect pet, it was interesting to read that beetles would make the best kinds of pets.
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Although I’ve never yearned to keep a pet beetle, I do feel like I spend a lot of time with them during the summer time. I feel like beetles come out constantly in the summer days and nights. They’re big beetles too! I wonder if they love hot weather or what specifically attracts them to the summer season. Also, beetles love to eat all the delicious peaches on our peach tree in the summer. As a result, we spray pesticides all over the tree. I wish there was a better way to get beetles off of the leaves of fruit trees because pesticides then negatively affect our health! But I am thankful to hear your perspective on how they are beneficial to society, because sometimes beetles really put the pest in pesticide.