1. three distinct body segments (head, thorax, abdomen),
2. one or two pairs of wings (rarely no wings),
3. three pairs of legs and
4. one pair of antennae.

KEY TO ADULTS

1. Winged (Fig. 1 A to N) . . . . 2

   Wingless (Fig. 1 O,P) . . . . 26

   
   

2. One pair of wings (Fig. 1 A,B)(flies: DIPTERA) . . . . 3

   Two pairs of wings, first pair often modified and covering the second (Fig. 1 C to N) . . . . 4

3. Long, many-segmented antennae; legs also long (Fig. 1 A) . . . . midges: Cecidomyiidae

   Short, three-segmented antennae; anal wing vein reaches wing margin (Fig. 2); body usually longer than 3 mm (Fig. 1B) . . . . root maggot flies: Anthomyiidae

   

4. Front pair of wings partially or completely thickened or leathery (Fig. 1H to N) . . . . 5

   Front pair of wings flexible and papery, sometimes clear (Fig. 1C to G) . . . . 18

5. Front pair of wings (wing covers) usually rigid, not transparent, and lacking veins (Fig. 1H, I); mouthparts chewing type (Fig 3A to C)(beetles: COLEOPTERA) . . . . 6

   Front pair of wings usually leathery, with veins (Fig. 1 J to N); mouthparts either chewing type (Fig 3A to C) or piercing-sucking beak (Fig. 3D) . . . . 13

   

6. Tarsi apparently three-segmenteed; antennae very short; antennae and head often hidden when viewed from above; body almost hemispherical in shape; often brightly colored (Fig 4A) . . . . lady beetles: Coccinellidae

   Tarsi apparently four- or five-segmented (Fig. 4 B to E) . . . . 7

   

7. All tarsi appear four-segmented (Fig. 4 B,C) . . . . 8

   Not as above . . . . 10

8. Head with a well-developed, elongated snout; elbowed antennae located about middle of snout; body size and shape variable (Figs. 1H, 4B) . . . . weevils, billbugs: Curculionidae

   Not as above . . . . 9

9. Long antennae at least one-half the length of the body; elongate body with parallel sides; body length 3 to 75 mm, but usually over 12 mm (Fig. 5A) . . . . long-horned beetles: Cerambycidae

   Antennae usually less than one-half the length of the body; body usually less than 12 mm long; shape and coloration variable (Figs. 4C, 5B) . . . . leaf beetles, flea beetles: Chrysomelidae

   

10. Tarsal formula 5-5-5 (Fig. 4D) . . . . 11

    Tarsal formula 5-5-4 (Fig. 4E) . . . . 12

11. Robust-bodied beetle; oval-elongate in shape and usually over 10 mm long; short 8- or 11-segmented antennae with plate-like segments at the tip which may form a compact ball (Figs. 4D, 5D) . . . . June beetles, May beetles: Scarabaeidae

    Elongate beetle 35 mm or less in length, usually 12 to 30 mm long; antennae appear serrated (Fig. 5C); mechanism present by which beetle can right itself when placed on its back by snapping two body segments together thereby propelling itself into the air (Fig. 6) . . . . click beetles: Elateridae

    

12. Pronotum, or front part of thorax, narrower than either head or elytra; body usually 3 to 30 mm long; antennae thread-like (Fig. 4E) . . . . blister beetles: Meloidae

    Pronotum not as above; threadlike, 11-segmented antennae; body 2 to 35 mm long, usually brown or black (Fig. 5E) . . . . darkling beetles: Tenebrionidae

13. Mouthparts chewing type (Fig 3A to C)(grasshoppers, crickets: ORTHOPTERA) . . . . 14

    Mouthparts extended into tube (Fig. 3D)(bugs: HEMIPTERA) . . . . 16

14. Hind legs modified for jumping (Fig. 7B,C); front legs not modified for digging; insect found above ground . . . . 15

    Hind legs not as above; front legs shovellike, modified for digging (Fig. 7A); soil insect with beady eyes . . . . mole crickets: Gryllotalpidae

    

15. Antennae short, seldom half as long as the body (Fig. 7B); female lacking elongate ovipositor; auditory organs present on sides of first abdominal segment . . . . grasshoppers: Acrididae

    Antennae long, usually as long as the body or longer (Fig. 7C); female's ovipositor elongate, cylindrical, or needle-shaped, but never bladelike; all tarsi three-segmented . . . . crickets: Gryllidae

16. Bug generally broad, shield-shaped; antennae five-segmented; large triangular scutellum; body usually longer than 7 mm (Fig. 1N) . . . . stink bugs: Pentatomidae

    Bug not shield-shaped; antennae four-segmented; body usually shorter than 7 mm . . . . 17

17. Membranous portion of forewing has two closed cells and a cuneus (Fig. 8A); body rarely longer than 10 mm . . . . plant bugs, lygus bugs: Miridae

    Membranous portion of forewing has four to five open, non-parallel veins (Fig. 8B); body usually less than 13 mm long . . . . seedbugs, chinch bugs: Lygaeidae

    

18. Wings caovered with tiny scales which resemble dust when smudged on one's finger (Fig. 9A); mouthparts usually long, threadlike (Fig. 9B)(moths, butterflies: LEPIDOPTERA) . . . . 19

    Wings without scales; mouthparts variable or lacking . . . . 21

    

19. Wingspan of 25 mm or more . . . . 20

    Wingspan 20 mm or less; labial palps large and distinctive, forming a fairly straight snoutlike projection (Fig. 10A) . . . . flour moths, grass moths: Phralidae

    

20. Wingspan of 25 to 50 mm; robust-bodied moths, dull in color; threadlike antennae (Fig. 10B,C) . . . . cutworm moths: Noctuidae

    Wingspan larger than 50 mm, more in range of 10 cm; large body tapering anteriorly and posteriorly; hummingbird-like feeding habits (Fig. 10D) . . . . sphinx moths: Sphingidae

21. Jumping insects; antennae short and bristlelike; piercing-sucking beak from head near first pair legs (Figs. 1F, 11A,B)(HEMIPTERA) . . . . 22

    Flying insect, may also run or flutter when disturbed; antennae filiform and threadlike; insect soft-bodied and less than 5 mm long (Fig. 1C to E) . . . . 24

    

22. Large pronotum covers head and extends back over the abdomen (Fig 1F) . . . . treehoppers: Membracidae

    Pronotum not as above . . . . 23

23. Hind tibiae with one or more rows of small spines (Fig. 11A); bug usually associated with chlorosis of many types of plants . . . . leafhoppers: Cicadellidae

    Hind tibiae with one or two stout spines and usually series or circle of spines at apex (Fig 11B); may be found in areas infested with spittle-producing nymphs . . . . spittlebugs: Cercopidae

24. Body with pair of cornicles, or "honey tubes," protruding from abdomen (Fig. 1E,P); slow-moving insect usually found in colonies (HEMIPTERA) . . . . aphids: Aphididae

    Body without cornicles . . . . 25

25. White insect (up to 2 mm) which resembles a tiny moth; often found on underside of plant leaves; flutters when disturbed, often flying in a spiral (Fig. 1D)(HEMIPTERA) . . . . whiteflies: Aleyrodidae

    Yellow, orange, brown, or black insect (up to 2 mm) which is slender and spindle-shaped with narrow, fringed wings (Fig. 1C); often found in buds of flowers, foliage, even corms; runs or flies when disturbed . . . . thrips: THYSANOPTERA

26. Four pairs of legs; only two major body segments . . . . 27

    Three pairs of legs . . . . 28

27. Abdomen connected to cephalothorax by a narrow, petiolelike structure; body (including legs) usually larger than 1 mm (Fig. 12A) . . . . spiders: ARANEIDA

    Abdomen broadly connected to cephalothorax, no constriction between these two body segments; body minute in size, usually about 0.5 mm long, but rarely as long as 1 mm (mites: ACARINA). The following characters are visible only under a microscope: Setae on tarsus 1 erect; no anterior tubercule on the propodosoma (Fig. 12B) . . . . spider mites: Tetranychidae

    

28. Pair of cornicles, or "honey tubes," extending from abdomen; body pearlike in shape; piercing-sucking beak arising from head near first pair of legs; slow moving; feeds in colonies on foliage; body usually less than 3 mm long (Fig. 1P) . . . . aphids: Aphididae

    No pair of cornicles; body slender and spindle shaped; rasping mouthparts; feeds on flowers, foliage, or corms; usually orange, black or brown; body less thatn 2 mm long . . . . common thrips: Thripidae