(insect without wings) |
| 32a. |
Small
soft-bodied insect living on terrestrial plants with the body encased
under a protective shield ('scale') or partly covered with white waxy
filaments or powder |
Hemiptera |
|
| 32b. |
Insect not like this |
33 |
|
|
| 33a. |
Thoracic legs absent or enclosed
in a membrane preventing any movement |
(Larvae and pupae of most
Orders of Endopterygota) |
|
| 33b. |
Thoracic legs present and fully
functional |
34 |
|
|
| 34a. |
Abdomen with false-legs
or prolegs (fleshy structures different from and additional to the
jointed legs of the thorax); insect caterpillar-like in general
appearance |
35 |
|
| 34b. |
Abdomen without prolegs;
insect not caterpillar-like |
37 |
|
|
| 35a. |
No more than 5 pairs of
prolegs |
Larvae of Lepidoptera |
|
| 35b. |
At least 6 pairs of
prolegs |
36 |
|
|
| 36a. |
Head with a single
small eye (ocellus) on each side |
Larvae of Hymenoptera |
|
| 36b. |
Head with several small
eyes (ocelli) on each side |
Larvae of Mecoptera |
|
|
| 37a. |
Insect living in a terrestrial
habitat or on the surface of water (not underwater) |
38 |
|
| 37b. |
Insect truly aquatic
(living underwater) |
Part 5 of the Key |
|
|
| 38a. |
Abdomen with cerci or other
terminal appendages (take care not to confuse terminal hairs or
bristles with cerci) |
39 |
|
| 38b. |
Abdomen without such
terminal appendages (though may have small appendages on proximal
segments or a pair of tubular outgrowths or cornicles near the hind
end) |
Part 4 of the Key |
|
|
| 39a. |
Abdomen with 6 segments
or fewer; usually with a forked terminal appendage (springing organ)
folded under the rear end when not in use |
Collembola |
 |
| 39b. |
Abdomen with more than
6 segments (usually 8 or more clearly visible); terminal appendages of
a different form |
40 |
|
|
| 40a. |
Antennae short and often
inconspicuous (at most about the same length as the head) |
41 |
|
| 40b. |
Antennae long and conspicuous
(usually much longer than the head) |
42 |
|
|
| 41a. |
Tarsi with at least
3 segments (usually 5-segmented) |
Phasmida |
|
| 41b. |
Tarsi with fewer than
3 segments (often reduced to single or paired claws on the end of each
leg) |
Larvae of Coleoptera |
|
|
| 42a. |
Hind-legs enlarged and
modified for jumping; insect grasshopper-like in general appearance |
Orthoptera |
|
| 42b. |
Hind-legs not modified for
jumping and usually similar in thickness to the middle-legs; insect
not grasshopper-like |
43 |
|
|
| 43a. |
Terminal appendages of abdomen
forming a pair of pincers or forceps |
44 |
|
| 43b. |
Terminal appendages of abdomen
not like this |
45 |
|
|
| 44a. |
Tarsi 3-segmented |
Dermaptera |
|
| 44b. |
Tarsi 1-segmented |
Diplura |
|
|
| 45a. |
Terminal appendages of
abdomen long (much more than half the length of the abdomen) |
46 |
|
| 45b. |
Terminal appendages of abdomen
short (less than half the length of the abdomen) |
48 |
|
|
| 46a. |
Abdomen with 3 terminal
appendages (paired cerci and a median filament) |
Thysanura |
|
| 46b. |
Abdomen with 2 terminal
appendages (cerci) |
47 |
|
|
| 47a. |
Tarsi 3-segmented;
terminal appendages of abdomen (cerci) unsegmented |
Dermaptera |
|
| 47b. |
Tarsi 1-segmented;
terminal appendages of abdomen (cerci) many-segmented |
Diplura |
|
|
| 48a. |
Tarsi usually 5-segmented
(though sometimes fewer on regenerated legs of Phasmida) |
49 |
|
| 48b. |
Tarsi with fewer than
5 segments on all legs |
52 |
|
|
| 49a. |
Front of head extended
downwards to form a beak-like structure with jaws (mandibles) at its
tip |
Mecoptera |
|
| 49b. |
No such beak-like extension
of the head |
50 |
|
|
| 50a. |
Prothorax much larger
than the head |
Dictyoptera |
|
| 50b. |
Prothorax and head of similar
size (prothorax at most only slightly larger than the head) |
51 |
|
|
| 51a. |
Cerci 8-segmented and
moderately long |
Grylloblattodea |
|
| 51b. |
Cerci unsegmented and
very short |
Phasmida |
|
|
| 52a. |
Tarsi usually 4-segmented |
Isoptera |
|
| 52b. |
Tarsi with fewer than 4
segments |
53 |
|
|
| 53a. |
Tarsi 1-segmented |
Diplura |
|
| 53b. |
Tarsi 2- or 3-segmented |
54 |
|
|
| 54a. |
Tarsi 2-segmented |
Zoraptera |
|
| 54b. |
Tarsi 3-segmented |
55 |
|
|
| 55a. |
Front tarsi with first
segment greatly swollen; cerci 2-segmented |
Embioptera |
|
| 55b. |
Front tarsi not
swollen; cerci unsegmented |
Phasmida |
|
|
