(insect with two pairs of wings) |
| 9a. |
Forewings partly or
entirely horny or leathery and forming stiffened covers for the membranous
hindwings |
10 |
|
| 9b. |
Both pairs of wings membranous
(flexible) and used for flying (though wings sometimes feather-like
rather than membranous or their membranous nature may be obscured by a
dense covering of hairs, scales or waxy powder) |
16 |
|
|
| 10a. |
Mouth-parts forming a
tube-like 'beak' (rostrum) for piercing and sucking (rostrum usually
folded backwards under the body when not in use) |
Hemiptera |
 |
| 10b. |
Mouth-parts with jaws
(mandibles) for biting and chewing |
11 |
|
|
| 11a. |
Forewings overlapping at least
a little in the centre-line and usually with many veins present |
12 |
|
| 11b. |
Forewings (elytra) meeting in
the centre-line and without veins (though elytra may have longitudinal
grooves or striae which should not be confused with veins) |
14 |
|
|
| 12a. |
Hind-legs enlarged and
modified for jumping; insect grasshopper-like in general appearance |
Orthoptera |
|
| 12b. |
Hind-legs not modified for
jumping and usually similar in thickness to the middle-legs; insect
not grasshopper-like |
13 |
|
|
| 13a. |
Prothorax much larger
than the head; cerci nearly always many-segmented and fairly prominent |
Dictyoptera |
|
| 13b. |
Prothorax and
head of similar size; cerci always unsegmented and very short |
Phasmida |
|
|
| 14a. |
Forewings (elytra)
long and covering all or most of the abdomen |
Coleoptera |
|
| 14b. |
Forewings (elytra) short and
leaving much of the abdomen exposed |
15 |
|
|
| 15a. |
Abdomen with a pair of
terminal pincers or forceps |
Dermaptera |
|
| 15b. |
Abdomen without
terminal pincers |
Coleoptera |
|
|
| 16a. |
Wings very narrow
without veins and fringed with long hairs (feather-like); tarsi 1- or
2-segmented (small slender insect often found in flowers) |
Thysanoptera |
|
| 16b. |
Wings broader with veins
present; if wings fringed with long hairs then tarsi comprised of more
than 2 segments (though wing veins of some insects may be much
reduced and hardly visible or partly obscured by hairs, scales or waxy
powder) |
17 |
|
|
| 17a. |
Hindwings noticeably smaller
than forewings |
18 |
|
| 17b. |
Both pairs of wings similar
in size or hindwings larger than forewings |
26 |
|
|
| 18a. |
Wings and much of the body
covered with white waxy powder; tiny insect usually less than 2-3 mm
long |
19 |
|
| 18b. |
No such powdery covering |
20 |
|
|
| 19a. |
Wings held flat over
the body at rest; mouth-parts forming a tube-like 'beak' (rostrum) for
piercing and sucking (rostrum usually folded backwards under the
body when not in use) |
Hemiptera |
|
| 19b. |
Wings held roof-wise
over the body at rest; mouth-parts with jaws (mandibles) for biting |
Neuroptera |
|
|
| 20a. |
Wings more or less
covered with minute scales; mouth-parts when present forming a coiled
proboscis or 'tongue' |
Lepidoptera |
|
| 20b. |
Wings usually transparent
(without scales though often hairy); mouth-parts not forming a coiled
proboscis |
21 |
|
|
| 21a. |
Forewings with many
cross-veins making a network pattern; abdomen with 2 or 3 long thread-like
terminal appendages |
Ephemeroptera |
|
| 21b. |
Forewings with relatively few
cross-veins; abdomen usually without or with only very short terminal
appendages (cerci) |
22 |
|
|
| 22a. |
Wings noticeably covered
with hairs; insect moth-like in general appearance |
Trichoptera |
|
| 22b. |
Wings not noticeably hairy
(though may be fringed with hairs or tiny surface hairs may be seen if
wings examined under a microscope or strong hand-lens) |
23 |
|
|
| 23a. |
Mouth-parts forming
a tube-like 'beak' (rostrum) for piercing and sucking (rostrum
usually folded backwards under the body when not in use; abdomen
sometimes with tubular outgrowths or cornicles near the hind end) |
Hemiptera |
|
| 23b. |
Mouth-parts with jaws
(mandibles) for biting and chewing |
24 |
|
|
| 24a. |
Tarsi 4- or 5-segmented;
hard-bodied insects with abdomen often constricted at its base into a
petiole or 'waist' (except Symphyta) |
Hymenoptera |
|
| 24b. |
Tarsi 2- or 3-segmented; small
soft-bodied insect |
25 |
|
|
| 25a. |
Antennae with at
least 12 segments |
Psocoptera |
|
| 25b. |
Antennae with only
9 segments |
Zoraptera |
|
|
| 26a. |
Tarsi 5-segmented |
27 |
|
| 26b. |
Tarsi 3- or 4-segmented |
29 |
|
|
| 27a. |
Wings noticeably covered
with hairs; insect moth-like in general appearance |
Trichoptera |
|
| 27b. |
Wings not noticeably
hairy (though tiny hairs may be seen if wings examined under a
microscope or strong hand-lens) |
28 |
|
|
| 28a. |
Front of head extended
downwards to form a beak-like structure with jaws (mandibles) at its
tip |
Mecoptera |
|
| 28b. |
No such beak-like
extension of the head |
Neuroptera |
|
|
| 29a. |
Tarsi 4-segmented |
Isoptera |
|
| 29b. |
Tarsi 3-segmented |
30 |
|
|
| 30a. |
Wings noticeably
hairy; front tarsi with first segment greatly swollen |
Embioptera |
|
| 30b. |
Wings not noticeably hairy;
front tarsi simple |
31 |
|
|
| 31a. |
Wings with many
cross-veins making a network pattern and held away from the body at
rest (either outstretched or folded vertically); antennae short and
inconspicuous |
Odonata |
|
| 31b. |
Wings with relatively
few cross-veins and folded flat over the body at rest; antennae long and
slender (longer than width of head) |
Plecoptera |
|
|
