Insect Orders
Insect Identification: The Basics
Figure 1: An Example of a Dichotomous Key
1a. Surrounds its body with a case of plant material (Figures a. and b.)
See 2
1b. Does not surround its body with plant material
See 3
a.
b.
2a. Case constructed of two pieces of leaves cut in a circular shape (Figure a.)
2b. Case constructed of rolled pieces of leaves ( Figure b.)
Tools and Methods for Collecting Aquatic Insects
Using the Key
A dichotomous key is a lot like a choose your own adventure story. In those kind of stories, after a block of text you had two choices. Each choice would take you somewhere different.
In a dichotomous key you will be presented with two choices. Each choice is described by text and periodically there are photographs which give an example. The pictures may not look exactly like your specimen, so do not use the pictures alone, always follow the text description.
Start with the first couplet, 1a. and 1b., and pick the phrase that best describes the insect you are attempting to identify. Under each desciption there is either a number or a name. The number directs you to the next couplet to read in the key. For example, if 1b. is chosen as the best description, the number 3 follows, taking you to couplet 3 with the choices 3a. and 3b. If a name is given instead, that is the name of an insect order. You can click on the link to go to the specific insect order page. Some numbers are links as well, this is because the key would load too slowly if it was all on one page. Figure 1 is the first two couplets of the key as an example.