Herpetology example

Cortland Herpetology Connection

Lizard and Snake Key

See also species distribution maps at the New York State
Amphibian and Reptile Atlas Project
website.

Key to the families of adult lizards and snakes in New York

1.a. Has legs lizards
1.b. Has no legs 2 (snakes)

2.a. Deep pit between nostril and eye Viperidae
2.b. No pit Colubridae

Key to the species of Lizards of New York

1.a. Scales smooth, flat, and shiny 2
1.b. Scales rough, keeled, and pointed Northern Fence Lizard
Sceloporus undulatus

2.a. Broad dark brown stripe on each side of body
bordered by thin light stripes above and below it,
making four light stripes in total, one postmental scale, young have blue tails
Coal Skink
Eumeces anthracinus
2.b. Often five light stripes which are wider than in
the coal skink, adult males may have stripes that
are faded and a reddish head, two postmental
scales, young have blue tails
Five-Lined Skink
Eumeces fasciatus

Key to the species of the family Viperidae of New York

Caution: Never attempt to hold any snakes in this family. All are venomous.

1.a. Body and head copper-colored, on body darker cross bands narrow in the middle of the back, no rattle on tail Copperhead
Agkistrodon contortrix
1.b. Body and head tan, brown, gray, or black, body with dark blotches or cross bands that do not narrow on the back, rattle often present on tail 2

2.a. Scales are large on center of head between eyes, body grayish with dark blotches, often with horizontal stripes on head Eastern Massasauga
Sistrurus catenatus
2.b. Scales are small on center of head between eyes, body tan, gray, yellowish, or black with dark cross bands, posterior part of body often darker than rest, head usually without markings Timber Rattlesnake<
Crotalus horridus

Key to the species of the family Colubridae of New York

1.a. Two scales between eye and nostril 2
1.b. Three or more scales between eye and nostril 4

2.a. 13 scale rows, scales smooth, pointed head Eastern Worm Snake
Carphophis amoenus
2.b. 15-19 scale rows, scales keeled 3

3.a. Belly is red, back is brown or gray, sometimes with faint lines, light line or spots on neck Redbelly Snake
Storeria occipitomaculata
3.b. Belly is white or pale pink, back is brown or gray, often with faint lines or spots, dark line or spots on neck Brown Snake
Storeria dekayi

4.a. Scales keeled 5
4.b. Scales smooth 11

5.a. Anal plate entire 6
5.b. Anal plate divided 8

6.a. Stripes on back, light line on side covering part of scale rows three and four, tail long, body thin Eastern Ribbon Snake
Thamnophis sauritus
6.b. Dorsal pattern with stripes or spots, light line on side begins on scale row two and does not reach scale row four, tail moderate 7

7.a. Short head, back is brown with light stripes, 17 scale rows at midbody, six upper labial scales Shorthead Garter Snake
Thamnophis brachystoma
7.b. Longer head, color variable spots or stripes, 19 scale rows at midbody, seven upper labial scales Eastern Garter Snake
Thamnophis sirtalis

8.a. Rostral upturned Eastern Hognose Snake
Heterodon platirhinos
8.b. Rostral not upturned 9

9.a. Heavily keeled scales, keels reach to tips of dorsal scales 10
9.b. Weakly keeled scales, keels not reaching tips of scales, body black with faint spotting pattern, 200+ ventral scales Black Rat Snake
Elaphe obsoleta

10.a. 19 rows of scales, yellowish stripe on side, four dark stripes along length of belly Queen Snake
Regina septemvittata
10.b. More than 19 rows of scales, head tall, body banded, blotched, or uniformly dark (in older individuals) Northern Water Snake
Nerodia sipedon

11.a. Anal plate entire, on back reddish brown or brown blotches on a grey or tan background Eastern Milk Snake
Lampropeltis triangulum
11.b. Anal plate divided 12

12.a. Yellow or orange ring around neck, uniformly gray or black above, yellow or orange on belly Northern Ringneck Snake
Diadophis punctatus
12.b. No neck ring 13

13.a. Brilliant green above when alive, 1 or 2 preocular scales, 15 dorsal scale rows, 115-144 ventral scales Smooth Green Snake
Liochlorophis vernalis
13.b. Shiny black dorsally and ventrally, 2 preoculars, 17 dorsal scale rows, 158-193 ventrals Northern Black Racer
Coluber constrictor

Much information for the turtle keys was derived from Reptiles of North America by Hobart Smith and E. D. Brodie, Jr.