How Many Insects Are There?

Abstract

WT HEN people ask, many inVY sects are they usually want answers to two different questions: How many kinds of insects are there? What is the total number of individual insects in the world? An honest answer to both is: nobody knows exactly. The number of kinds, or species, is so great that entomologists cannot keep an accurate count, except for small groups. The number of kinds that have already been described and named is estimated by various scientists at 625,000 to 1,500,000. No one can even guess when the big tally will be finished. For such huge groups as beetles and flies, an exact count may never be possible, although generally the numbers of the smaller groups can be tallied more accurately. Workers in the division of insect identification of the Department of Agriculture estimate that by the end of 1948 approximately 686,000 different species of insects had been described and named for the entire world (Table I). In addition were some 9,000 species of ticks and mites, which are not true insects but look like insects to the lay person. About two-fifths of the known kinds of insects are beetles. Moths and butterflies, ants, bees, wasps, and true flies comprise another two-fifths. For North America north of Mexico, the latest figures show nearly 82,500 kinds of insects, plus 2,613 kinds of ticks and