Dichotomous Keys - Text Format.
Arthropods - Key B: Arthropods with Six Legs, with Tiny or Missing Wings.

Tips: Only adult arthropods are included, and certain uncommon orders are not included. To use a key, read both descriptions in a couplet (for instance, 1a and 1b). Decide which sounds most like your critter, and move to the next couplet indicated. Should you reach a dead-end, use the numbers in parentheses to backtrack until you reach a couplet that you felt unsure about, and try following the other path. Some orders are found more than once in the keys, because the arthropods occur in different forms.

1a Does not resemble a twig. . . . . . . . . . go to 2
1b Slow-moving, resembles a twig
(Walking sticks)
2a 1a Body very soft. . . . . . . . . . go to 3
2b 1a Body not exceptionally soft. . . . . . . . . . go to 8
3a 2a Mouthparts hidden within head, usually with a springlike structure (furcula) on the underside of the abdomen used for jumping
3b 2a External mouthparts, without a springlike structure on the underside of the abdomen. . . . . . . . . . go to 4
4a 3b Visible projections at the tip of the abdomen. . . . . . . . . . go to 5
4b 3b No visible projections at the tip of the abdomen. . . . . . . . . . go to 6
5a 4a Long flattened body, tip of abdomen with 2 - 3 long tails (cerci, and if a third tail is present, a median caudal filament)
5b 4a Small pear-shaped body, tip of abdomen has two short projections (cornicles), some individuals have wings
6a 4b Usually found in colonies with many individuals (soldier caste), some of which have very large heads and mandibles (soldier caste) or mouthparts that look like a tube (nasuti caste)
6b 4b Tiny insects that may be found in groups of many individuals, but they all have the same kind of mouthparts . . . . . . . . . . go to 7
7a 6b Chewing mouthparts, relatively long antennae, when individuals have wings the wings never have fringes of hair
(Bark lice)
7b 6b Sucking mouthparts, fairly short antennae, adults may actually have barely visible wings with fringes of hair
8a 2b Body with a narrow "waist," antennae usually have a bend in the middle
(Ants & Wingless wasps)
8b 2b Body without a narrow "waist", antennae don't usually have a bend in the middle. . . . . . . . . . go to 9
9a 8b Tiny jumping parasites found on mammals or birds, where they suck blood
9b 8b Not found on mammals or birds, chewing mouthparts. . . . . . . . . . go to 10
10a 9b Prominent "pincers" at the tip of the abdomen (cerci)
10b 9b Without "pincers" at the tip of the abdomen

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