Beetle or Bug?

Bugs and beetles are so commonly mistaken for each other, and one might think it a matter of little consequence, but the record must be set straight in the name of science! We can’t have our children blithely thinking beetles are bugs and vice versa, now can we? When it comes to beetles and bugs, the similarities abound, but the differences are in the details. Below are the main characteristics that distinguish beetles from true bugs. When it comes to identifying them in the wild, you may notice that not all these aspects are immediately apparent, which is why there are several ways to differentiate the two. Look for all the clues before you declare your mystery insect to be a beetle or a bug!

Beetles (Coleoptera)

Chewing mouthparts that consume a wide range of plant and animal material
Two layers of wings: top wings, called elytra, are hardened into a protective structure for the hindwings, which are membranous and fold beneath the elytra when not in use
Undergoes complete metamorphosis, which is comprised of four stages: embryo, larva, pupa, and adult
Wing covers always meet in a straight line down the middle of the insect’s back when closed

True Bugs (Hemiptera)

Piercing mouthparts that ingest a pure liquid diet, both from plant and animal sources, which folds back between its legs
If wings are present, they are membranous and partially thickened, sometimes with another pair of hindwings
Undergoes incomplete metamorphosis, in which the juvenile is simply a smaller version of the adult, without wings if it is a winged insect
The wings of the true bug cross over on the insect’s back in a cross-hatch or diamond pattern

Based on what you just learned, can you tell which of the insects below are beetles and which are bugs?