Chap. 30 



ARTHROPODS INSECTS, SPIDERS, AND ALLIES 



593 



Table 30.1 

 Number of Described Species of Insects, Ticks, and Mites at the End of 1948* 



Order 



Common . Names 



World 



Anoplura 



Coleoptera 



Collembola 



Corrodentia 



Dermaptera 



Diptera 



Embioptera 



Ephemeroptera 



Hemiptera 



Hymenoptera 

 Isoptera 

 Lepidoptera 

 Mallophaga 

 Mecoptera 

 Neuroptera 

 Odonata 

 Orthoptera 

 Plecoptera 

 Protura 

 Siphonaptera 

 Thysanoptera 

 Thysanura 

 Trichoptera 

 Zorapterat 

 Total 



Acarina 



Sucking lice (true lice) 



Beetles, weevils, twisted winged insects 



Springtails 



Booklice, barklice 



Earwigs 



Flies, mosquitoes, gnats 



Embiids 



Mayflies 



True bugs and Homoptera (cicadas, leafhoppers, 



aphids. scale insects) 



Ants, bees, wasps 



Termites ("white ants") 



Butterflies and moths 



Biting lice (bird lice) 



Scorpionflies 



Lacewings, ant lions, dobsonflies 



Dragonflies, damselflies 



Grasshoppers, crickets, roaches, mantids, katydids 

 Stoneflies 



Fleas 



Thrips 



Bristletails, "Silverfish" 

 Caddisflies 



Ticks 



Mites 



250 



277,000 



2.000 



1,100 



1.100 



85,000 



149 



1,500 



55,000 



103,000 



1,717 



112,000 



2,675 



350 



4,670 



4,870 



22,500 



1,490 



90 



1,100 



3.170 



700 



4,450 



19 



685,900 



440 

 8,700 



North 



America, 



north of 



Mexico 



62 



26,676 



314 



120 



18 



16.700 



8 



550 



8,742 



14,528 



41 



10,300 



318 



66 



338 



412 



1.015 



340 



29 



238 



606 



50 



921 



2 



82.394 



113 

 2,500 



* Source: Insects, U.S.D.A. Yearbook of Agriculture. 1952. 



t Zoraptera includes Corrodentia or booklice. Embioptera — minute tropical species, and 

 Protura — minute and rare species. 



sea, insects have been land-adjusted for millions of years. In their immature 

 stages, mosquitoes can thrive in brackish water but with rare exceptions, in- 

 sects keep away from the sea. Those of several groups live in fresh water while 

 they are immature and some others remain there as adults but all breathe air 

 as adults and are essentially terrestrial. 



Insects have spread almost all over the earth, in abundance in all tropical 

 and temperate countries and as parasites living on the warm bodies of birds 

 and mammals, in arctic and antarctic lands. One or another kind of insect 

 makes a living in every conceivable location in and out of buildings, in every 

 part of all kinds of plants, in forests and open fields. Insects are persistently 

 active, feeding, and flying, constantly urged to shift their places by competition 



