This figure shows the locations of four landmarks on the right cercus of Enallagma ebrium, the species that shows the most basic morphological plan for the Enallagma cerci. Enallagma cerci all have the basic shape of a two-tined fork. The end of the superior tine is identified by the light and dark blue dots, and the end of the inferior tine is identified by the red and pink dots. These landmarks are placed on each of the computer models to allow the viewer to orient the cerci of each species relative to one another and relative to their correct position on the body. Three other landmarks (not shown) identify the surface where the cercus is attached to the 10th abdominal segment (green being the most medial point, light brown the most dorsolateral point, and dark brown the most ventrolateral point).