Beetles vs. Bugs

Beetles and bugs are types of insects that are classified into two different orders. There are 400.000 species of beetles that are members of the order Coleoptera, and around 75.000 species of bugs that belong to the order Hemiptera. Beetles and bugs can be found all over the world. They inhabit both terrestrial and aquatic habitats. Many species of beetles and bugs are classified as agricultural pests. Beetles and bugs are not close relatives and thanks to numerous unique features, each group of insects can be easily identified:

Wings

Beetles have hard and leathery forewings called elytra and long membranous hind wings hidden below. Hind wings are visible only when beetles are flying. Forewings of bugs, called hemelytra, are made of two dissimilar halves. They are hard at the base and membranous at the tip. Hind wings of bugs are also membranous and shorter than the forewings.

Geographical Distribution

Beetles have wider geographical distribution and ability to survive in various habitats (except in the polar regions) because of their hard forewings which protect body like a shell.

Antennas

Bugs have antennas made of 4 to 5 segments, while beetles have antennas made of usually 11 segments.

Mouth Apparatus

Bugs have needle-like mouth apparatus designed for extraction of juices (sap or nectar) from the plants. Some bugs feed on the liquids obtained from the animal tissues. Beetles have hard, tooth-like mouthparts designed for grasping, cutting, chewing and biting. Their diet is based on various plants and animals.

Locomotion

Most beetles are able to fly. Ground beetles and beetles that inhabit caves and deserts have lost their ability to fly. They move by walking. Aquatic beetles are excellent divers. Bugs, on the other hand, can fly, walk, jump, glide over the surface of the water or even swim, depending on the species and type of habitat. Some bugs do not move at all. They spend their entire life attached to the host plant.

Life Cycle

Beetles undergo 4 developmental stages in their life: egg, larva, pupa and adult insect (complete metamorphosis). Larva, also known as grab, has hardened head and voracious appetite. It quickly grows in size. Pupa is dormant stage and it ends with fully developed adult beetle. Unlike them, bugs have incomplete metamorphosis. Newly hatched bugs are called nymphs and they look like miniature version of adult insects. They develop wings and attain adult size after several instars (periods in between the molting).

Association with Humans

344 species of beetles and large bugs such as cicadas are consumed as delicacy around the world. Beetles such as ladybugs and ground beetles eliminate pests from the gardens and fields. Dung beetles play important role in nutrient cycling and in enrichment of soil with minerals.