American Vertebrate Dichotomous Key
1a. Animal has smooth or rough surface with no feathers or fur …………………... ………………….2
1b. Animal has feathers or fur ………………….………………….…………………. ……………… 22
2a. Animal that does not have tail ………………….………………….……………… ...………………3
2b. Animal that has a tail, fins, or a relatively large, round shell (carapace) on the
back ………………….………………….………………….……………………….. ……...………….6
3a. Amphibian that has moist skin ………………….………………….……………… ………………….4
3b. Amphibian that has dry skin that is bumpy, and has dark green, brown, or
black blotches on a light background, large protruding eyes, a round muzzle,
Great Plains
and bumps on the neck behind the eyes ………………….………………….
………………toad
4a. Amphibian that has many relatively large spots ………………….…………… ………………….5
4b. Amphibian that has a relatively uniform coloration of grayish tan with a few
Great Plains
small scattered black spots, as well as a pointed muzzle, a small head, and a
narrowmouth
fold of skin across the back of the head behind the eyes ………………….
………….toad
5a. Amphibian that is gray with many darker blurry spots, and has a round
muzzle, protruding eyes slit vertically in bright light, and a black spur at the
base of each hind foot ………………….………………….………………….
5b. Amphibian that is tan or gray with distinct dark spots, and has a round
muzzle and protruding eyes as well as a raised fold or ridge of skin on either
side of the back that runs from behind the eyes down to the thighs …………
………… - plains
spadefoot
- plains leopard
frog
6a. Animal that has legs ………………………………………………………………. ………………….7
6b. Animal that does not have legs …………………………………………………… ………………..15
7a. Animal that has a relatively large, round carapace and/or scales over the
back ………………………………………………………………………………
7b. Animal that has no carapace and has moist, smooth skin with no scales, as
well as several vertical grooves on each side of the body and light spots or
bars on a dark background ………………………………………………………
…………………8
…- eastern tiger
salamander
8a. Animal that has a relatively round hard or leathery carapace ………………… ………… ………9
8b. Animal that has smooth or rough scales over the body and has no carapace ………………..12
9a. Turtle that has a hard carapace ………………………………………………….
………………...10
9b. Turtle that has a tan leathery carapace with distinct spots and without scales,
a short tail, a very pointed muzzle, and paddle-like front feet
for swimming ……………………………………………………………………….. - spiny soft-shell
10a. Turtle that has yellow, orange, and/or red markings on the carapace, head,
and legs ……………………………………………………………………………… ………………..11
10b. Large turtle that is uniformly brown, and has a large head with a hooked
beak, a flat carapace, and a long serrated……………………………………… ………- common
snapping turtle
11a. Turtle that has a relatively flat carapace that is brown or green with red
markings at the edge, a brown or green head and legs with yellow lines, and
a short tail …………………………………………………………………………… ...- painted turtle
11b. Turtle that has a highly domed carapace that is brown with yellow or orangeyellow lines across its surface, a dark head and legs with yellow or orange
spots, and a short tail ……………………………………………………………… ……- ornate box
turtle
12a. Reptile that has rough scales over the body ……………………………………
12b. Reptile that has smooth scales over the body …………………………………
………………..13
………………..14
13a. Lizard that has a brown back with darker spots and a white line down the
medial part of the back, as well as extremely rough, raised scales on its body
with large spines projecting from the dorsal part of the head ………………… ...- Texas horned
lizard
13b. Lizard that is gray to brown with dark irregular bands, spots, or lines, and has
rough raised scales on its body and no spines on the head
- fence lizard
14a. Lizard that appears to have lines of spots due to flat, smooth, shiny scales on
its body that are light with dark border ………………………………………….. ….- Great Plains
skink
14b. Lizard that has greenish blue to yellow stripes running down the dark green
to brown back and small, smooth, grainy scales across the back ………….. ………- six-lined
racerunner
15a. Animal has fins …………………………………………………………………….. ………………..51
15b. Animal does not have fins …………………………………………………………. ………………..16
16a. Reptile that has no rattle on the tail ……………………………………………… ………………17
16b. Reptile that has a rattle at the posterior part of the tail, and is gray or tan with
dark gray or brown blotches ………………………………………………………. …. massasauga
17a. Reptile that has smooth scales ………………………………………………….
17b. Reptile that has keeled scales ………………………………………………….
……………...18
……………….20
18a. Snake that has a single uniform color over body and tail ……………………… ……………...19
18b. Snake is black and white arranged in bands, rings, stripes, patches, spots and
speckles. Head has same pattern. …………………………………………………. ..- common king
snake
19a. Snake that has a grayish or bluish black head, body, and tail with a distinct
orange or yellow ring around the neck ………………………………………….. - ringneck snake
19a. Snake that has a tan body and tail with a black head ………………………….
- plains
blackhead snake
20a. Snake that has lines running down the length of body ………………………..
……………….21
20b. Snake that is covered with blotches, that are dark brown on a gray to yellow
or tan head, body, and tail, and has a sharply upturned muzzle. This snake
will inflate the sides of its neck when threatened (like a cobra.) ……………… ……….- western
hognose snake
21a. Snake that has a yellow stripe running down the medial of the back and on
each peripheral part of the back, with dark spots on a red background
between the stripes ……………………………………………………………….. - common garter
snake
21b. Snake that has a white or yellow stripe running down the medial of the back
and on the peripheral part of the gray or brown body and tail, with a gray or
brown head …………………………………………………………………………. …..- lined snake
22a. Animal has feathers ……………………………………………………………….. ……………… 23
22b. Animal has fur ……………………………………………………………………… ………………..42
23a. Bird that is most often found in water when not flying …………………………. ………………..24
23b. Bird that is usually not found in water ……………………………………………. ………………..27
24a. Bird that swims in water …………………………………………………………… ………………..25
24b. Bird that wades in shallow water, has long legs and a long neck and is bluegray in coloration with a dark crown …………………………………………….. …….- great blue
heron
25a. Swimming bird that has green on the head and may or may not be brightly
colored on the body ……………………………………………………………….. ………………..26
25b. Swimming bird that has a brown and white head and is colored black, white,
gray, and/or brown ………………………………………………………………… - northern pintail
26a. Swimming bird that is brightly colored with green, yellow, red, black, and
white
26b. Swimming bird that is primarily colored with brown, buff, black, and white
feathers with a green head and white neck ring
- wood duck
- mallard
27a. Bird that is almost totally dark brown or black (may have a little bright red
and/or yellow) ………………………………………………………………………. ………………..28
27b. Bird that is not totally dark brown or black ………………………………………. ………………..29
28a. Large black or dark brown bird with a bare, red head ………………………….. ..- turkey vulture
28b. Medium-sized perching bird, often found around marshes, that has a black
……- redbody with red epaulets that may be edged with yellow
winged
blackbird
29a. Brightly colored bird with bright blue, red, and/or orange with black and/or
white …………………………………………………………………………………
29b. Bird not colored as above …………………………………………………………..
30
33
30a. Bird that has bright orange and white with black or blue ……………………….
30b. Bird that has bright red with black and/or white ………………………………….
31
32
31a. Medium-sized perching bird that is bright orange, white, and black ………….
31b. Medium-sized perching bird that is bright blue, orange, and white …………..
32a. Medium-sized perching bird with a crest that is bright red with a black face
and red bill …………………………………………………………………………..
32b. Medium-sized perching bird that has patches of black and white over its body
with a bright red head ……………………………………………………………..
- Baltimore
oriole
- eastern
bluebird
- northern
cardinal
- red-headed
woodpecker
33a. Relatively large predatory bird that hunts small or medium-sized mammals
and has a strong, hooked bill and sharp, curved talons ………………………
33b. Medium-sized or small perching bird or ground-dwelling bird ………………
34
37
34a. Nocturnal bird with a large, round head with large eyes that face forward …
34b. Diurnal bird that has eyes on the sides of the head ………………………….
35
36
35a. Medium-sized bird that is gray, tawny, and white with a striking heart-shaped
face and dark eyes ………………………………………………………………..
35b. Large bird that is gray, brown, tawny, and/or white with a cat-shaped head
(due to conspicuous ear tufts) and yellow eyes …………………………….
- barn owl
- great horned
owl
36a. Large bird that is darkly colored with a white face, a rufous chest, and a
darkly streaked white front …………………………………………………..
36b. Relatively small bird that is multicolored with rufous and black-barred back,
streaked rufous or buff front, blue-gray wings, distinct gray, white, buff, bluegray, and/or rufous head …………………………………………………………..
- Swainson's
hawk
37a. Medium-sized or small ground-dwelling bird ……………………………………
37b. Relatively small perching bird ……………………………………………………
38
39
38a. Medium-size, round bird with a short neck and striking white, black, and
rufous head, as well as a brown, rufous, and gray body with a short tail …….
38b. Medium-size, ground-dwelling bird with a thin neck and a small head with a
pale face and relatively long bill, as well as a brown and buff body with long
legs ……………………………………………………………………………………
39a. Relatively small perching bird that is primarily black, white, and gray ………
39b. Relatively small perching bird that is gray with a yellow stripe above the eye
and a yellow patch on the cheek, as well as a black V below the throat and a
yellow chest and rufous shoulders ………………………………………………
40a. Relatively small perching bird that has a black head or cap [top of the head]
40b. Relatively small perching bird that has a brown, back, head, and breast with
a pale pink belly, underwing, and flanks, with a extremely long black and
white tail that is split ……………………………………………………………
41a. Relatively small perching bird that has a black head, a dark gray back, a
white throat and belly, and a black tail with a white tip …………………..
- American
kestrel
- northern
bobwhite
- upland
sandpiper
40
- dickcissel
41
- scissor-tailed
flycatcher
- eastern
kingbird
41b. Small perching bird that has a black cap and throat, white nape and cheeks,
white front and buff flanks, greenish gray back, and a gray tail and wings …
42a. Mammal that is primarily brown, buff, and/or gray and may also have some
white or black …………………………………………………………………….
42b. Mammal that is only black and white, having striking coloration with a black
head with a narrow white stripe down the middle of the face, a black body
with two white stripes down the back that come together over the neck and
head (forming a V shape), and a bushy black tail often with a white tip …..
43a. Mammal that has a tail that is relatively uniform in coloration or bicolored with
dark on the top and light on the bottom ………………………………………….
43b. Mammal that has rings around its tail, and has a grayish or brown body with
furred tail that has black and gray rings, large round pinna, and a distinctive
black mask around the eyes …………………………………………………….
44a. Mammal that has relatively long legs and a body that is high off the ground ..
44b. Mammal that has relatively short legs and/or a body that is close to the
ground ………………………………………………………………………………
45a. Relatively large mammal that has relatively uniform body coloration of gray
with buff underparts, a medium-length bushy tail with a black tip, large
pointed pinna, and a long muzzle with a black nose ………………………….
45b. Large mammal that has relatively uniform body coloration of tan or brown
with white underparts, a relatively short brown tail that flashes white from
underneath when lifted, large pinna, a long muzzle with a white band around
a black nose, and may have antlers ………………………………………………
46a. Mammal that has a long tail that is at least half of its body length and
relatively round pinna ……………………………………………………………..
46b. Mammal that has a tail that is considerably shorter than half of its body
length and/or long pinna ………………………………………………………….
47a. Mammal that has relatively uniform rusty brown coloration with a long, bushy,
rust-colored tail, large eyes, and round pinna ………………………………….
47b. Small mammal that is grayish to brown with white underparts with a long thin
tail, as well as large black eyes, round pinna, and white feet ………………..
48a. Mammal that has a very short tail and long pinna …………………………….
48b. Mammal that has a relatively short tail and short pinna ……………………..
49a. Medium-sized mammal that has gray and brown coloration with a rustcolored neck, as well as long pinna, large black eyes, and a distinctive tail
that looks like a cotton ball ………………………………………………………
49b. Medium-sized mammal that has gray, buff, and black coloration with very
long pinna and an extremely short tail that is black on top, edged with white,
with a black stripe extending a short distance up the back …………………..
- black-capped
chickadee
43
- striped skunk
44
- northern
raccoon
45
46
- coyote
- white-tailed
deer
47
48
- eastern fox
squirrel
- white-footed
deer mouse
49
50
- eastern
cottontail
- black-tailed
jackrabbit
50a. Relatively small mammal that is uniformly brown and has large claws and a
relatively short, thinly haired tail …………………………………………………
50b. Relatively large mammal that has a relatively flat body colored gray, buff, and
black, a short yellowish tail, large front claws, and a distinctive face that is
black with three white stripes, one in the middle and one by each eye …….
- plains pocket
gopher
- American
badger
51a. Body noticeably covered with round scales, able to move dorsal fin…………
51b. Scales not covering body or tooth-shaped scales …………………………….
52
58
52a. Fish has single dorsal fin………………………………………………………….
52b. Fish has two or more dorsal fins, joined or separated…………………………
53
56
53a. Body of fish more than four times as long as broad (top to bottom): front
edge of dorsal fin far back on body; mouth large, hinge back of eye………….
53b. Body of fish less than four times as long as broad: front edge of dorsal fin
about midway between head and tail; mouth not large, hinge in front of eye
54
55
54a. Fish has lines forming netted design on body: fins not spotted ……………..
54b. Body of fish covered with yellow spots; fins spotted………………………….
- Dark Pickerel
- Northern Pike
55a. Mouth of fish turned downward: barbels absent; dorsal fin not elongated…
55b. Mouth of fish not turned downward: barbels present; dorsal fin elongated…
- White Sucker
- Carp
56a. Body of fish has forked dorsal fin, the anterior spiny and the posterior soft..
56b. Body of fish has two dorsal fins united, forming an anterior spiny portion and
a posterior soft portion
57a. Top of fish head concave, forming a hump in front of dorsal fin; distinct dark
vertical bands on body………………………………………………………………
57b. Top of fish head not as concave, body sloping to dorsal fin and not forming a
hump; no distinct dark vertical bands on body. ………………………………….
58a. Body of fish cartilaginous, long, slim and either lacking fins or has very small
fins. Jawless ………………………………………………………………………...
58b. Body of fish cartilaginous, long, with immovable dorsal fins and / or tail. Has
a jaw…………………………………………………………………………………...
57
- Yellow Perch
- Walleye
59
60
59a. Fish has several barbels on chin, mouth not disk or funnel-like ……………….
59b. Fish mouth disk or funnel-like, no barbels on chin ………………………………
- Hagfish
- Lamprey
60a. Body of fish kite-like if viewed from the top ………………………………………
60b. Body of fish not kite-like if viewed from the top………………………………….
61
63
61a two hornlike appendages on front………………………………………………….
- Pacific Manta
Ray
62
61b no hornlike appendages…………………………………………………………….
62a. small dorsal fin present near tip of tail, no stinging spine………………….
62b. no dorsal fin near tip of tail, stinging spine. Tail about 2 times body length….
End of tail banded with black and white.
63a. Mouth at front of muzzle
63b. mouth on underside of head
64a. top half of caudal fin about the same
size as bottom half
64b. top half of caudal fin different in size
than bottom half .
65a. long point on the end of muzzle
65b. muzzle without long point
- Common Skate
- Blue Spotted
Stingray
- Whale Shark
64
- White Shark
65
- Saw Shark
- Dog Fish Shark