1. Insects with wings. The forewings are often in form of hard wing covers. Go to 2

Wings absent or represented only by very small pads.Go to 18

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2. With only one pair of wings. Wings are always membranous. Go to 3

With two pair of wings. The front pair of wings are often hard wing covers with the hind wings folded underneath. Go to 4

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3.End of abdomen with two or three conspicuous projecting filaments. Order Ephemeroptera (Mayflies) (Top of Key)

End of abdomen without filaments.Order Diptera (Flies & Mosquitoes) (Top of Key)

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4. Forewings in the form of hard wing covers meeting in a straight line down the center of the back. No veins apparent in wing covers. Under the wing covers is a set of membraneous wings.Go to 5

Forewings not hard. They are either parchment-like membranous, or covered with scales or hairs. Forewings do not meet in a straight line. Wing veins usually evident.Go to 6

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5. Tip of abdomen with a pair of prominent foreceps-like appendages. Front wings very short.Order Dermaptera (Earwigs) (Top of Key)

Tip of abdomen without forceps. Wing covers covering most if not all the abdomen.Order Coleoptera (Beetles) (Top of Key)

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6. Forewings mostly or all parchment-like. Base of forewing may be parchment-like with the remainder membranous.Go to 7

Forewings all membraneous, hairy, or covered with scales.Go to 9

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7. Mouth parts in the form of piercing or sucking beak.Go to 8

Mouth parts not in the form of a beak, but fitted for chewing.Order Orthoptera (Grasshoppers) (Top of Key)

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8. Basal portion of forewing parchment-like with the tip membraneous. Wings usually flat on back. Beak arising from the front of head.Order Hemiptera (True Bugs) (Top of Key)

Wing all of one texture. Wings usually roof-shaped over back. Beak arising from the rear portion of the head near the first pair of legs.Order Homoptera (Hoppers & Cicadias) (Top of Key)

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9. Wings covered with scales. Often in colored patterns.Order Lepidoptera (Moths & Butterflies) (Top of Key)

Wings not covered with scales.Go to 10

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10. Wings narrow, blade or tassel-like, and fringed with hairs. Tarsus ending in a baglike structure.Order Thysanoptera (Thrips) (Top of Key)

Wings not blade or tassel-like. Tarsus without baglike structure.Go to 11

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11. Mouth parts in the form of a piercing and sucking beak.Order Homoptera (Hoppers & Cicadias) (Top of Key)

Mouth parts fitted for chewing.Go to 12

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12. Wings veins netlike.Go to 13

Wings with few veins, not netlike.Go to 15

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13. Antennae very short and inconspicuous.Go to 14

Antennae conspicuous, composed of many segments.Go to 16

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14. Hind wings small. Tip of abdomen with two or three long filaments extending backwards.Order Ephemeroptera (Mayflies) (Top of Key)

Fore and hind wings about equal size. No filaments at tip of abdomen.Order Odonata (Dragonflies & Damsel Flies) (Top of Key)

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15. Wings covered with fine, long hairs and held roof-like over the abdomen when resting. antennae very long.Order Trichoptera (Caddisflies) (Top of Key)

Wings membraneous, not held roof-like over abdomen. May be held horizontally when resting. Antennae short.Order Hymenoptera (Bees, Wasps & Ants) (Top of Key)

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16. Wing veins may be membraneous and faint. Body antlike. Fore and hind wings same size and shape.Order Isoptera (Termites) (Top of Key)

Wings veins well developed and apparent. Body not antlike. Fore and hind wings the same size.Go to 17

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17. Cerci present. Tarsi with two or three segments. Wings held horizontally and second pair folded like a fan when at rest.Order Plecoptera (Stoneflies) (Top of Key)

No cerci present. Tarsi with five segments. Wings held rooflike and not folded when at rest.Order Neuroptera (Lacewings) (Top of Key)

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18. Tip of abdomen with two or three appendages directed backward.Go to 19

Tip of abdomen with no appendages.Go to 20

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19. Abdomenal appendages thick and rigid. In the form of forceps.Order Dermaptera (Earwigs) (Top of Key)

Abdominal appendages delicate, flexible.Order Thysanura (Silverfish) (Top of Key)

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20. Small insects, less than 1/4 inch long.Go to 22

Larger insects, more than 1/4 inch long.Go to 21

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21. Body noticeably pinched at base of abdomen. Antennae bent.Order Hymenoptera (Bees, Wasps & Ants) (Top of Key)

Body not noticeably pinched at the base of the abdomen. Antennae not bent.Order Isoptera (Termites) (Top of Key)

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22. A very small (less than 1/8 inch long) insect with an appendage at the tip of abdomen curling under and forward.Order Collembola (Springtails) (Top of Key)

A small insect without curving appendage at tip of abdomen.Go to 23

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23. Body flattened from side. Legs very large and fitted for jumping. Abdomen distinctly segmented.Order Siphonaptera (Fleas) (Top of Key)

Body flattened from top to bottom.Go to 24

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24. Legs with conspicuous hooks at ends. Head much narrower than abdomen. Piercing and sucking mouth parts. Found mostly on mammals.Order Anoplura (Sucking Lice) (Top of Key)

Legs without conspicuous hooks. Head almost as wide as abdomen. Chewing mouth parts. Usually found on birds.Order Mallophaga (Chewing Lice) (Top of Key)