3. Usually with forked spring (furcula - Fig. 11)on abdomen.
Size small, 2-4mm. Always lacking apical
abdominal cerci. If furcula absent, size and body
shape are characteristic of order .. Collembola
— Furcula always absent. Body size larger, shape various 4
4. Apex of abdomen with long cerci (Fig. 13) and lacking
ventral abdominal styliform appendages, or if
ventral styliform appendages present, cerci are
short ...................................................................5
— Cerci short or lacking; abdominal styliform appendages
always absent ...........................................6
5. Apex of abdomen with 3 filamentous cerci (silverfish)
..........................................................Thysanura
— Apex of abdomen with 2 cerci, either forceps-like (Fig.
12) or short and segmented ................. Diplura
6. Large unsegmented forceps-like structures at apex of
abdomen(earwigs) ........................ Dermaptera
— Cerci (when present) neither forceps-like nor
unsegmented .....................................................7
7. Large insects, usually > 25mm in length; antennae
frequently very long and slender ......................8
— Small insects, usually < 12mm in length .................9
8. 4-segmented tarsi ....................................Orthoptera
— 5-segmented tarsi ...................................... Phasmida
9. Tube-like structures (cornicles) (Fig. 14 )protruding
posteriorly from 4th to last abdominal segment;
OR body covered with waxy filaments or a scale
.........................................................Homoptera
— Cornicles absent AND no scale or waxy filaments
covering body ...................................................10
10. Abdomen constricted to narrow waist where it joins
thorax (bees, wasps, ants, sawflies) ..................
.................................................... Hymenoptera
— Abdomen not constricted into narrow waist ...........11
11. Front legs with enlarged first segment (Fig. 15)
(basitarsus), which is modified for production of
silk (webspinners) .......................... Embiidina
— First tarsal segment not enlarged ...........................12
12. Mouthparts (rasping-sucking) contained in a short,
cone-like beak; wings when present often with
fringe of hairs (Fig. 16); size