How to Use a Dichotomous Key of Turtles
- 1). Observe the turtle prior to using the dichotomous key and make note of special features of the turtle such as if the shell is hard or soft, coloration on the shell, carapace (which is the underside of the shell), head shape, tail length and any other features that may be able to identify the turtle species.
- 2). Go to the first question of the dichotomous key which typically for turtles will be, "Is the shell hard or soft?" The answer to the question will lead to the next set of questions. Go to the number or page associated with the answer.
- 3). Answer the next observational question about the turtle. All questions will be a yes-no or an either/or type of question such as, "A wide and prominent yellow, orange, or red stripe or blotch behind eye" or "An absent or narrow yellow stripe behind eye." Select which option best describes your turtle and move on to the next set of questions. Note any areas on the key that are confusing or not as descriptive of your turtle.
- 4). Continue answering questions about the turtle until the dichotomous key provides the species of turtle you may have. Find a picture of the turtle that the key has identified as your turtle. Compare it to your turtle. If it matches, then you have found the correct species. If it does not match, go back to questions you were uncertain about and follow a different branch of questions to see if you can locate your species.
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