1.
- All scales smooth, flat, rounded posteriorly .....Western Skink, Plestiodon skiltonianus
- Scales either granular, keeled, or pointed .....2
2.
- Longitudinal skin fold on each side of body .....3
- No longitudinal skin folds on sides .....4
3.
- Dark stripes along edges of belly scales .....Northern Alligator Lizard, Elgaria coerulea
- Dark stripes on center of belly scales .....Southern Alligator Lizard, Elgaria multicarinata
4.
- Spiny ridges or spines at rear of head .....Pygmy Short-horned Lizard, Phrynosoma douglasii
- No ridges or spines at rear of head .....5
5.
- Gular fold with granules .....Common Side-blotched Lizard, Uta stansburiana
- No gular fold with granules .....6
6.
- Scales on rear of thigh granular (not overlapping); throat with mottled blue patches .....Sagebrush Lizard, Sceloporus graciosus
- Scales on rear of thigh imbricated (overlappping); throat with solid blue patches .....Western Fence Lizard, Sceloporus occidentalis
Adapted by Dennis Paulson from key in Nussbaum,R. A., E. D. Brodie, Jr., and R. M. Storm. 1983. Amphibians & Reptiles of the Pacific Northwest. Univ. Press of Idaho, Moscow. Names revised December 2013.