This key consists of pairs of opposite choices or descriptive statements. To use this key, start at the first page and read the two statements. Decide which statement best describes the organism and click on your choice. This will take you to the next pair of statements. Repeat the procedure until the macroinvertebrate is identified. You can then click on the macroinvertebrate name and additional information concerning the identification, life history, and pollution sensitivity of the macroinvertebrate will be provided.

If you reach a point in the selection of descriptive statements at which neither of the statements apply, you can work your way back through the preceding pairs of statements and perhaps reconsider the choices. In some cases, the additional information about the individual macroinvertebrates will be helpful. In others, you will find that you are unable to identify the particular macroinvertebrate and you will have to identifiy it as "unknown" unless you can find an aquatic biologist or more information to help you with the identification.

Some macroinvertebrates (such as some caddisfly larva) will be found in a protective case of sand, small sticks, or other material. You may find it necessary to remove these cases in order to make an identification.

For some specimens, magnification with a hand lens will be needed to see the identification characteristics.

After you have made an identification you can return to the first page of the key to identify additional specimens. Note: drawings in the key are not to scale.

Go to first page of key.