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Reptiles and Amphibians of Yosemite National Park (1946) by Myrl V. Walker

A SIMPLIFIED KEY*
TO THE REPTILES AND AMPHIBIANS OF
YOSEMITE NATIONAL PARK

* In an effort to make this key workable for a majority of the Park visitors, it has been made as simple as possible. Diagnostic characters used are those most easily observed and understood. They do not follow natural relationships or conform to the technical keys ordinarily used by zoologists. This key will therefore apply only to the amphibians and reptiles found in Yosemite National Park, and and can not be used to identify species found outside this area.

1a. Vertebrates with body covering smooth. Usually moist. No scales, feathers, hairs, claws or nails Amphibians 2

1b. Vertebrates with body covering of dry scales. No feathers or hair Reptiles 10

2a. Amphibians with an elongate body and a tail which is present, throughout life
Salamanders 3

2b. Amphibians with adult body short. No tail in adults Toads and Frogs 5

3a. Salamanders with skin slightly rough—reddish brown above—not spotted
SIERRA NEWT— Triturus sierrae Twitty p. 5

3b. Salamanders with skin very smooth—more or less spotted 4

4a. Body brownish black with a few yellow or orange spots
SIERRA NEVADA SALAMANDER—Ensatina sierrae Storer p. 6

4b. Body chocolate or slate color with numerous grayish spots
MOUNT LYELL SALAMANDER—Hydromantes platycephalus Camp p. 7

5a. Adults with parotoid glands present Toads 6

5b. Adults with parotoid glands absent 7

6a. Toads with large parotoid glands. Space between glands wider than one gland
CALIFORNIA TOAD—Bufo boreas halophilus Baird and Girard p. 10

6b. Toads with small parotoid glands. Space between glands smaller than one gland
YOSEMITE TOAD—Bufo canorus Camp p. 10

7a. Toes with expanded adhesive discs at their tips
PACIFIC TREE TOAD—Hyla regilla Baird and Girard p. 12

7b. Toes without expanded adhesive discs at their tips Frogs 8

8a. Frogs with red coloring on inner side of hind legs
CALIFORNIA RED-LEGGED FROG—Rana aurora draytonii Baird and Girard p. 13

8b. Frogs with yellow coloring on inner side at hind legs 9

9a. Heel of hind leg reaching beyond nostril when leg is bent forward
CALIFORNIA YELLOW-LEGGED FROG—Rana boylii boylii Baird p. 14

9b. Heel of hind leg not reaching beyond nostril when leg is bent forward
SIERRA YELLOW-LEGGED FROG—Rana boylii sierra Camp. p. 14

10a. Reptiles with four legs 11

10b. Reptiles without legs 20

11a. Body covered above and below with a bony shell, commonly called carapace and plastron
WESTERN POND TURTLE—Clemmys marmorata Baird and Girard p. 17

11b. Body covered with large or small scales Lizards 12

12a.
Lizards with a series of femoral pores (a row of glandular pores on underside of the thigh) 13

12b. Lizards without femoral pores 18

13a. Head adorned with a number of short sharp horns
CALIFORNIA HORNED LIZARD—Phrynosoma blainvillii frontale Van Denburgh p. 21

13b. Head without horns 14

14a. Belly scales large. In eight longitudinal rows
CALIFORNIA WHIP-TAILED LIZARD—Cnemidophorus tessellatus tessellatus Say p. 24

14b. Belly scales small and numerous Sceloporus 15

15a. Scales on back of thigh not keeled
MOUNTAIN LIZARD—Sceloporus graciosus graciosus Baird and Girard p. 19

15b. Scales on back of thigh strongly keeled 16

16a. Blue belly patches confluent (fused) with blue throat patches. Not separated by a lighter band
TENAYA BLUE-BELLIED LIZARD—Sceloporus occidentalis taylori Camp p. 19

16b. Blue belly patches not confluent but separated from blue throat patch 17

17a. Adult males with lateral blue throat patches distinct or slightly fused. (Never fused in yng.)
WESTERN FENCE LIZARD—Sceloporus occidentalis occidentalis Baird and Girard p. 19

17b. Adult males with single central blue throat patch. Never divided
PACIFIC BLUE-BELLIED LIZARD—Sceloporus occidentalis biseriatus Hallowell p. 19

18a. Dorsal scales smooth. No raised ridge running lengthwise of scale
YOSEMITE SKINK—Eumeces gilberti gilberti Van Denburgh p. 25

18b. Dorsal scales keeled Gerrhonotus 19

19a. Dorsal scale rows usually 14. Iris of eye yellow (live specimens)
SAN DIEGO ALLIGATOR LIZARD—Gerrhonotus multi-carinatus webbii Baird p. 23

19b. Dorsal scale rows usually 16. Iris of eye dark (live specimens)
SIERRA ALLIGATOR LIZARD—Gerrhonotus coeruleus palmeri Stejneger p. 23

20a. Snakes with pupil of eye vertical 21

20b. Snakes with pupil of eye round 23

21a. Dorsal body scales strongly keeled. Tail with rattle
PACIFIC RATTLESNAKE—Crotalus viridus oreganus Holbrook p. 31

21b. Dorsal body scales smooth 22

22a. Tail short and stubby. Skin loosely fitting
PACIFIC RUBBER SNAKE—Charina bottae bottae Blainville p. 29

22b. Tail not short or stubby. Skin normal
SPOTTED NIGHT SNAKE—Hypsiglena ochrorhyncha ochrorhyncha Cope p. 41

23a. Dorsal body scales keeled 24

23b. Dorsal body scales smooth. Not keeled 27

24a. Body scales in 29 or more rows
PACIFIC GOPHER SNAKE—Pituophis catenifer catenifer Blainville p. 34

24b. Body scales in 19 to 21 rows Garter Snakes 25

25a. Garter snakes without conspicuous lateral or dorsal light lines
SIERRA NEVADA GARTER SNAKE—Thamnophis ordinoides couchii Kennicott p. 37

25b. Garter snakes with conspicuous lateral and dorsal light lines 26

26a. With reddish spots or bars on sides
CALIFORNIA RED-SIDED GARTER SNAKE—Thamnophis sirtalis tetrataenia Yarrow p. 37

26b. Without reddish spots or bars on sides
MOUNTAIN GARTER SNAKE—Thamnophis ordinoides elegans Baird and Girard p. 37

27a. Tail short. Ending in a sharp point or spine
SHARP-TAILED SNAKE—Contia tenius Baird and Girard p. 44

27b. Tail not short. Normally long and slender 28

28a. Anal plate divided 29

28b. Anal plate single. Not divided 31

29a. A single light neck ring or nuchal collar present
CORAL-BELLIED RINGNECK—Diadophis amabilis pulchellus Baird and Girard p. 31

29b. Neck ring not present 30

30a. Body with conspicuous lateral light lines
CALIFORNIA STRIPED WHIPSNAKE—Coluber lateralis Hallowell p. 35

30b. Body with lateral light lines. Belly yellow
WESTERN BLUE RACER—Coluber constrictor mormon Baird and Girard p. 35

31a. Body marked with rings or cross bands of black and white only
CALIFORNIA KING SNAKE—Lampropeltis getulus california Blainville p. 42

31b. Body marked with rings or cross bands of black, white and red
SIERRA CORAL KING SNAKE—Lampropeltis multicincta multicincta Yarrow p. 42

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