There are actually, well over 20,000 different species of Beetles found throughout the world. Beetles make up the insect segment, Coleoptera, which means in Greek, ‘sheath wings’. It refers to a beetle’s elytra, which form a sheath (a blanket) for much of the upper body. The order coleopteran is the largest order of insects in the world. Nearly 40 percent of all insect species belong to this order. The order is divided into about 150 families, which comprise of on their own thousands of different varieties of species. This read will describe some of the major beetle families. The scientific name of the family will appear in parentheses after the common name.
These are the different species of beetles, in which each will be discussed further separately below:
Weevils (Curculionidae)
Leaf beetles: (Chrysomelidae)
Ground beetles: (Carabidae)
Rove beetles: (Staphylinidae)
Scarabs: (Scarabaeidae)
Click beetles: (Elateridae)
Predacious living beetles: (Dytiscidae)
Ladybugs: (Coccinellidae)
Fireflies: (Lampyridae)
Weevils
Also known as billbugs consist of more than 40,000 species. They are the largest beetle family in the world. The mouths of adult weevils are located at the tip of their long snouts, which is used to bore into fruits, seeds, plants etc. The larvae have no legs, thus they must feed inside the fruits and nuts in which they have been placed by their parent beetle. Many weevils are seen as pests in the farming community as they destroy crops. Most weevils are brown or gray, but some there are some tropical species which are brightly covered.
Leaf beetles
These beetles total more than 25,000 different species. Most leaf beetles have the ability to fly. When they grow disturbed, they may drop to the ground and play dead for awhile. Both the larvae and adults eat leaves and act as serious crop pests. The Colorado potato beetle is one of the most common beetle pests in North American in which it is responsible for causing great damage to potato crops.
Ground beetles
They number more than 20,000 species. The adults have long legs and long antennae. Most of these species of beetles hide during the day and search for food at night. Both the adults and larvae prey on other animals. Some species of ground beetles have been brought to the U.S to prey on crop eating insects and pests. The bombardier beetle, for example is an unusual ground beetle, as it defends itself by squirting two chemicals, both from the end of its body. The chemicals mix to produce a hot puff of gas that act to repel the beetles’ enemies.
Rove beetles
These make up more than 20,000 species. Rove beetles have unusually short elytra, which make them appear as earwigs. Earwigs, however, have sharp pincers at the tip of their abdomen. Some rove beetles turn up the tip of their abdomen as if they could sting. Most larvae and adult prey on other animals or eat dead or decaying compost, or other materials.
Scarabs
Consists of about 20,000 species. Both dung beetles and tumblebugs are well known scarabs. They feed on dung (solid feces of animals). They often shape masses of dung into a ball, and bury it in soil. Females lay an egg in the ball of dung. June bugs and Japanese beetles are two types of scarabs that eat crop plants.
Click beetles
Have a total of 8,000 species. These slender beetles can jump and posses the ability to make a clicking sound if disturbed, acting as a good deterrent against enemies. They do this by means of the hook like part that locks the first and second segments of the thorax together. By building pressure up between these two body segments and then releasing the hook, the beetle’s body will jerk and continue with a clicking sound. Adult click beetles are commonly drawn to lights at night.
Predacious living beetles
These make up about 4000 species. They live in and or near fresh water. They prey on snails, tadpoles, and smaller fish. The larvae, which also live in the water, have a long, soft body. The adult beetle can swim by moving their hind legs together like boat oars. When under water, the adults breathe the air trapped within their body hairs, or beneath their elytra.
Ladybugs
Otherwise called ladybirds, and lady beetles. These number some 4000 different species. Adult ladybugs have oval bodies. Many are orange, red, or yellow and have black spots along the cover. The larvae look like miniature lizards and some are brightly colored. Both adults and larvae hear insects that attack trees, shrubs, and fruit and vegetable crops. In the fall, ladybugs gather in large groups to hibernate together under leaves commonly found at tree bases, or under stones and random debris.
Fireflies
Also called lightning bugs, which total about 1900 species. Most species of beetles here produce a chemical light in their abdomen through a process called ‘bioluminescence’. The firefly produces this light to find other fireflies, in which to mate with. Each species use a special pattern of flashes to distinguish each other. Some adult fireflies do not feed. Some eat pollen or nectar. The larvae prey on small snails and other small insects. The glowing larvae and the flightless females of some species are known as glow worms.
Source
World Book, Inc. 1994. Volume 2 (B). “Kinds of beetles”. World Book Encyclopedia.