Wyoming's Reptiles:
The Turtles, Snakes & Lizards


You can easily identify the reptiles of Wyoming using the following
photos, videos and identification guide to the species of
turtles, lizards & snakes found in Wyoming.

There is a place I go when I want to look for rattlesnakes. It's an escarpment with a bluff 40 feet high, a buttress extending for miles along the edge of the tableland. The interface at the bottom of the cliff is clean and sharp; a boundary separating the source of the calving material from the slabs, boulders and rubble which flow down the slope and accumulate at the base, growing it wider and extending it out onto the basin floor. It's a good home them here ... click here for the full excerpt

There is a place I go when I want to look for rattlesnakes. It's an escarpment with a bluff 40 feet high, a buttress extending for miles along the edge of the tableland. The interface at the bottom of the cliff is clean and sharp; a boundary separating the source of the calving material from the slabs, boulders and rubble which flow down the slope and accumulate at the base, growing it wider and extending it out onto the basin floor. It's a good home them here. Exposed layers of ancient sediment are fractured with cuts and cracks which create passageways leading deeper to winter dens. The large reflective surface of the wall bounces back solar radiation and scatters the energy all along the slope, adding heat to the land and lengthening the reptile's summer. The protective cover of rock and shrub shelters a larder of rabbit babies and little servings of birds. And near the end of the slope, where it tapers into prairie, are thick deposits of alluvial soil, fostering mature stands of sagebrush and supporting populations of ground squirrels and varieties of mice, voles and moles.

I do not go to these snakes to wrangle with them, and it is neither their pleasant company I seek nor the delight of their danger; in fact, to the contrary, it is not my intention to disturb them at all, but rather discover them unalarmed and to watch these vipers in a natural state. For me, to move through this place without attention would be to stumble from a lack of respect, like trying to be at the place where I'm going and not the place where I'm at. So, while on this hillside, I require of myself to try hard, do the best I can, and focus. I hunt for the sheen scattered by scales when touched by the light; I pass when it differs and dulls from the grit on a rock. Here I seek the calm of single-mindedness, where only a search image pattern will register and all else is a blur.


The photos and identification key below were taken from the Field Guide to the Amphibians and Reptiles of Wyoming. Click here for the Free Online Version. Click here for the Key to the Amphibians of Wyoming.

You can click on an image to enlarge it and display it in its own frame. You can also click on the Common Name link to go to the web page for that species account.


Wyoming Turtles

Western Spiny Softshell Turtle

1a. Carapace leathery and flattened; snout elongated; feet with 3 claws: Western Spiny Softshell Turtle.

1b. Carapace of hardened plates and not flattened; snout not elongated—key 2.





Eastern (Common) Snapping Turtle

2a. Carapace ridged, usually encrusted with algae: Eastern (Common) Snapping Turtle.

2b. Carapace not ridged or algae encrusted—key 3.





Ornate Box Turtle

3a. Plastron hinged allowing closure against carapace; brown vermiculations against light tan or yellow background: Ornate Box Turtle.






Western Painted Turtle

3b. Plastron not hinged; with elaborate and mirrored pattern against red background: Western Painted Turtle.







Wyoming Lizards

1a. Most or all dorsal body scales keeled and not smooth or granular—key 6.

1b. Most or all of the dorsal body scales smooth or granular and not keeled—key 2.


2a. Longitudinal stripes 3 or none; tail as long as or shorter than length of body—key 5.

2b. Longitudinal stripes 5 or more; tail much longer than body; juveniles with blue tail—key 3.


Prairie Racerunner

3a. Scales becoming keeled along tail; gular fold present; six pale longitudinal stripes; southeastern distribution: Prairie Racerunner.

3b. Tail scales not keeled; cylindrical body with shortened legs; southeastern or southwestern distribution: Skinkskey 4.




Northern Manylined Skink

4a. Dorsal midline stripe pale and narrow with many alternating dark and light stripes along the sides; southeastern distribution: Northern Manylined Skink.





Northern Manylined Skink

4b. Midline stripe dark and wide with a single pale dorsolateral stripe along each side; southwestern distribution: Great Basin Skink. *Image use permission granted, © Lesile Schreiber.





Great Plains Earless Lizard

5a. Dorsal scales all granular; longitudinal stripes present; without external ear opening; southeastern distribution: Great Plains Earless Lizard.






Northern Tree Lizard

5b. Midline row of keeled and irregular shaped scales; dorsal background of darker wavy lines; Sweetwater County: Northern Tree Lizard.






Greater Shorthorned Lizard

6a. Head and body covered with greatly enlarged and pointed scales; oval shaped body with short tail: Greater Shorthorned Lizard.

6b. Scales not enlarged and pointed; tail about as long as body—key 7.




Northern Sagebrush Lizard

7a. With black shoulder patch; black-white-black striped pattern on rear of thigh: Northern Sagebrush Lizard.

7b. Without black shoulder patch; lacking black-white-black striped pattern on thigh—key 8.





Prairie Lizard

8a. With a prominent gray midline stripe with white dorsolateral stripes; southeastern distribution: Prairie Lizard.

8b. With dorsal blotches or markings but lacking longitudinal stripes—key 9.





Red-lipped Plateau Lizard

9a. Dorsal pattern of two rows of zigzag slashes; narrow distribution corridor along hogback ridge from Colorado to near Douglas: Red-lipped Plateau Lizard.

9b. Without dorsal zigzag pattern; adults in breeding condition lacking red coloration on lips and snout; southwestern distribution—key 10.




Northern Plateau Lizard

10a. Dorsal body scales all keeled; dorsal pattern lacking or of irregular blotches or speckling; Sweetwater and Carbon County: Northern Plateau Lizard.






Northern Tree Lizard

10b. Row of keeled and irregular shaped scales running midline through granular scales of dorsal surface; dorsal background of dark wavy lines; Sweetwater County: Northern Tree Lizard.






Wyoming Snakes

1a. Tail not ending in a rattle; neck about as thick as head and body; dorsal pattern various—key 3.

1b. Tail ending in a rattle; large triangular shaped head with narrow neck; dorsal blotches; venomous pit viperskey 2.


Prairie Rattlesnake

2a. Dorsal blotches with white border; adults larger than 30 inches TL; east of the Continental Divide and in Carbon County and eastern Sweetwater County: Prairie Rattlesnake.






Midget Faded Rattlesnake

2b. Dorsal blotches with black border; adults less than 28 inches TL; central Sweetwater County: Midget Faded Rattlesnake.






3a. Dorsal surface not uniform but with a pattern of stripes, blotches, or rings—key 7.

3b. Dorsal pattern mostly uniform and lacking stripes, blotches, or rings—key 4.


Northern Rubber Boa

4a. Dorsal color tan to light brown; head with black cap; tail tapering to a point; anal plate divided; only known from Glendo State Park: Plains Black-headed Snake. *Image use permission granted, © Gary Nafis.



4b. Dorsal color green, greenish brown or olive green; head without black cap—key 5.



Smooth Greensnake

5a. Dorsal color bright green; belly white; adults less than 20 inches TL: Smooth Greensnake.





5b. Dorsal color greenish brown to olive green; belly cream to yellow; adults greater than 20 inches—key 6.


Northern Rubber Boa

6a. Belly cream to pale yellow; dorsal color greenish brown to olive green and of small, smooth scales; tail blunt; anal plate entire, not divided; juveniles same uniform pattern as adults; northwestern and north central mountains and foothills: Northern Rubber Boa.




Eastern Yellow-bellied Racer

6b. Belly yellow; dorsal color green to dull green or olive; adults greater than 24 inches TL; scales smooth but larger and not beadlike; tail tapering to a point; anal plate divided; juveniles less than 20 inches have mixed pattern of dorsal blotches: Eastern Yellow-bellied Racer.





Pale Milksnake

7a. Background pattern of red, black and yellow rings; scales smooth and not keeled; anal plate entire: Pale Milksnake.

7b. Dorsal pattern of blotches or stripes, not rings; scales keeled—key 8 .



8a. Dorsal pattern of longitudinal stripes—key 11.

8b. Dorsal pattern of blotches, not striped—key 9.


Plains Hog-nosed Snake

9a. Rostral scale upturned; anal plate divided: Plains Hog-nosed Snake.

9b. Rostral not upturned; anal plate entire—key 10.






10a. Rostral scale higher than wide; distribution range east of Continental Divide: Bullsnake.






Great Basin Gopher Snake

10b. Rostral scale as high as it is wide; southwestern distribution: Great Basin Gopher Snake.






Black Hills Red-bellied Snake

11a. Belly red; adults less than 16 inches TL; northeastern distribution: Black Hills Red-bellied Snake.

11b. Belly not red; longer than 18 inches—key 12.





Black Hills Red-bellied Snake

12a. Black or darkened dorsal midline stripe about 4-5 scales wide; Lower Green River: Desert Striped Whipsnake.*Image use permission granted, © Deborah Ambrose.


12b. Midline stripe orange or pale yellow and about 2-3 scales wide; Gartersnakes—key 13.



Plains Gartersnake

13a. Midline stripe orange or bold yellow; scales of upper jaw with black bars; lateral stripes on 3rd and 4th row: Plains Gartersnake.

13b. Midline stripe white or pale yellow; lacking black bars on labial scales; lateral stripes on 2nd and 3rd row—key 14.




Wandering Gartersnake

14a. Background gray or olive brown without red and black checkerboard pattern: Wandering Gartersnake.

14b. Red and black checkerboard pattern between midline and lateral stripes—key 15.





Red-sided Gartersnake

15a. Anterior margin of ventral scales with black spots; east of Continental Divide: Red-sided Gartersnake.







Valley Gartersnake

15b. Margin of ventral scales without black spots, head and dorsal background darker; western distribution: Valley Gartersnake.