Beetles, Pacific Northwest
The Beetles are the most diverse order of living organisms and their numbers are extraordinary with more than 350,000 named species that represent about 40% of all insects and 30% of all animals. There are at least six times as many beetles as vertebrate species and 90 times more than the number of all mammals.
The order is divided into four suborders and about 150 families. Polyphaga is by far the largest suborder, containing 85% of the known species, including rove, scarabs, stag, metallic wood boring, click, fireflies, blister, meal worms, ladybirds, leaf , longhorn beetles, weevils and many more kinds of beetles.
Perhaps the single most important factor in the success of them is the development of the elytra or armored fore-wings that are leathery and hard, they are not used in flight but are a sheath that covers the more delicate flying wings when they are not in use. In Flight, the elytra are held perpendicular to the body and are used as airfoils.
They live in almost every conceivable terrestrial and freshwater habitat and even in some marginal marine ones. Many species live in fresh water, either in the larva stage or in both larval and adult stages. Many adults have ventral patches of fine setae that trap air bubbles for use in breathing under water.
Most species of beetles are predators. They are of immense ecological and economic importance. Many are vital in the cycles of decomposition of plant and animal matter. Others are predators of insects and other invertebrates that damage crops and other plants. On the other hand many beetles feed on the foliage and roots of plants, causing much damage to crops and they can kill huge tracts of valuable forests in a short time.