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LEPTOTYPHLOPIDAE
Leptotyphlopidae
- Blind Snakes
- No transversely elongated scales present on belly
- Eyes covered with scales
- Worm-like
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CROTALIDAE
Agkistrodon
- Cottonmouth and Copperheads
- No Rattle
- Pit between eye and nostril
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CROTALIDAE
Sistrurus
- Massasauga Rattlesnakes
- Top of head covered with large scales
- Rattle on head of tail
- Pit between eye and nostril
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CROTALIDAE
Crotalus
- RattlesnakesTop of head covered with small scales,(or not behind eyes)
- Rattles
- Pit between eye and nostril
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BOIDAE
Charina
- Rosy Boas
- No paired elongate scales between lower labials of right and left side
- No pit between eye and nostril
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ELAPIDAE
Micruroides
- Coral Snake
- Ring on neck red
- A pair of short permanently erect grooved fangs in anterior part of upper jaw
- All US species black red and yellow
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ELAPIDAE
Micrurus
- Coral SnakeRing on neck black
- A pair of short permanently erect grooved fangs in anterior part of upper jaw
- All US species black red and yellow
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COLUBRIDAE
Heterodon
- Hog-nose snakes
- Rostral turned upward and keeled
- Anal Plate divided
- Keels
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COLUBRIDAE
Storeria
- Common Brown Snake
- No loreal
- Rostral not turned upward and keeled
- Anal Plate divded
- Keels
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COLUBRIDAE
Virginia
WARNING SHITTY SNAKE
- Earth Snakes
- More than 13 scale rows, less than 27
- Nasal Plate divided
- No belly spots
- Rounded pupil
- 6 upper labials
- Less than 8 lower labials
- No preoculars
- Loreal and 2 prefrontals in contact with eye
- Anal plate not/divided
- Smooth Scales
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COLUBRIDAE
Regina
- Queen Snakes
- 19 Scale rows
- Ventrals fewer than 140
- 5-7 Supralabials
- 9-11 lower labials
- 1/2 preoculars
- 2/3 postoculars
- Anal plate divided
- Strongly Keeled scales
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COLUBRIDAE
Seminatrix
- Swamp Snakes
- Fewer than 60 caudals
- No dark line from rostral to last upper labial
- 8 upper labials
- 17 scale rows
- 2 internasals
- 1 preocular
- Loreal
- Anal Plate divided
- Smooth some keeled scales
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COLUBRIDAE
Opheodrys
- Rough Green Snake (blue or brown in alcohol
- Posterior chin shields about as long as anterior chin shields
- Cauduals more than 65
- Nasal plate entire
- No ring on neck
- No black spots on belly
- 1 anterior temporal
- Lower preocular not wedged between upper labials
- Rostral normal
- 7 upper labials
- 7 or 8 lower labials
- 17 scale rows
- 1/2/3 preoculars
- Loreal
- Anal plate divided
- Smooth Scales
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COLUBRIDAE
Drymobius
- Neotropical racers
- 9 upper labials
- 10 or 11 lower labials
- dorsal color dark with a light spot on each scale
- middorsal scales faintly keeled
- More than 100 rows of caudals
- 17 scale rows
- 1 or 2 preoculars
- 2 internasals
- loreal
- Anal plate divided
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COLUBRIDAE
Nerodia
- Water Snakes
- 20-23 scale rows
- 8-10 supralabials
- 2/3 postoculars
- 1/2 preoculars
- 2 internasals
- Loreal
- Anal plate divided
- Strongly keeled scales

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COLUBRIDAE
Clonophis
- Kritland's snake
- Lower labials 7
- 1 preocular
- 3 postocular
- 19 Scale rows
- 2 internasals
- Loreal
- Anal plate divided
- Keeled scales
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COLUBRIDAE
Pituophis
- Gopher Snakes
- 27 or more scale rows
- Usually 4 prefrontals
- Anal Plate not divided
- Keeled Scales

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COLUBRIDAE
Thamnophis
- Garter Snakes
- 8 or more lower labials
- Rounded Pupil
- No suboculars
- Rostral normal
- Fewer than 27 scale rows
- 2 prefrontal
- Anal Plate not divided
- Keeled scales
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COLUBRIDAE
Tropidoclonion
- Lined Snakes
- Double row of black belly spots
- Fewer than 8 lower labials
- Rounded Pupil
- No suboculars
- Rostral normal
- Fewer than 27 scale rows
- Anal plate not divided
- Keeled scales
- 2 prefrontals

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COLUBRIDAE
Rhinocheilus
- Long-nose snakes
- Most caudals entire
- Anal plate not divided
- Smooth scales
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COLUBRIDAE
Stilosoma
- Short Tailed Snakes
- No Loreal
- Pupil round
- All or most caudals divided
- Anal Plate not divided
- Smooth Scales
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COLUBRIDAE
Cemophora
- Scarlet Snakes
- 6-7 Upper labials
- 8 Lower labials
- Light Ventral surface without marking
- Loreal
- Rounded Pupil
- Caudals divided
- Anal Plate not divided
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COLUBRIDAE
Arizona
- Glossy Snakes
- 8 Upper labials
- 12-15 Lower labials
- Light Ventral surface without marking
- Loreal
- Rounded Pupil
- Caudals divided
- Anal Plate not divided
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COLUBRIDAE
Drymarchon
- Indigo Snakes
- 17 Scale rows
- Ventral surface with some dark markings
- Loreal
- Rounded Pupil
- Caudals divided
- Anal Plate not divided

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COLUBRIDAE
Lampropeltis
- King and Milk Snakes
- More than 17 scale rows
- Ventral surface with some dark markings
- Loreal
- Rounded Pupil
- Caudals divided
- Anal Plate not divided
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COLUBRIDAE
Carphophis
- Worm Snakes
- 13 scale rows
- Nasal plate entire
- 5 upper labials
- No preoculars
- Loreal and prefrontal in contact with eye
- Anal plate divided
- Smooth scales
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COLUBRIDAE
Salvadora
- Patch-nosed snake
- Rostral Much enlarged with free lateral edges
- 2 or 3 preoculars
- Loreal
- Anal plate divided
- Smooth Scales

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COLUBRIDAE
Coluber
- Racers
- Scale rows at posterior end of body 15
- 2 or 3 anterior temporals
- Lower preocular very small, wedged between upper labials
- Rostral normal
- 2 or 3 preoculars
- Loreal
- Anal plate divided
- Smooth Scales
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COLUBRIDAE
Masticophis
- Whipsnakes
- Scale rows at posterior end of body 11-13
- 2 or 3 anterior temporals
- Lower preocular very small, wedged between upper labials
- Rostral normal
- 2 or 3 preoculars
- Loreal
- Anal plate divided
- Smooth Scales
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COLUBRIDAE
Diadophis
- Ring-necked Snake
- Nasal plate divided
- Ring on neck/black spots on belly
- 1 anterior temporal
- lower preocular not wedged between upper labials
- Rostral normal
- 2/3 preoculars
- Loreal
- Fewer than 19 Scale rows
- Anal Plate divided
- Smooth Scales
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COLUBRIDAE
Contia
- Sharp Tailed Snakes
- Each ventral with a dark anterior border
- Usually a light stripe on 4th or 5th scale row
- Posterior chin shield much shorter than anterior chin shields
- less than 65 caudals
- Less than 17 scale rows
- 1 preocular
- Loreal
- Anal plate divided
- Scales Smooth

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COLUBRIDAE
Sonora
- North American ground snake
- Normal snout
- No nasal valve
- Ventral surface uniform light color, possible black rings
- Posterior chin sheild much shorter than anterior chin shields
- less than 65 caudals
- Less than 17 scale rows
- 1 preocular
- Loreal
- Anal plate divided
- Scales Smooth
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COLUBRIDAE
Rhadinaea
- Pine woods snakes
- More than 60 caudals
- A dark line form rostral through eye to last upper labial
- 7 upper labials
- 17 scale rows
- 1 preocular
- Loreal
- Anal Plate divided
- Smooth scales
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COLUBRIDAE
Chilomeniscus
- Sand Snakes
- 13 Scale rows
- No loreal
- Anal Plate divided
- Smooth Scales

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COLUBRIDAE
Chionactis
- Shovel nose snakes
- Snout flattened, shovel like
- nasal valve present
- 15 Scale rows
- Ventral surface uniform light color, possible black rings
- Posterior chin sheild much shorter than anterior chin shields
- less than 65 caudals
- 1 preocular
- Loreal?
- Anal plate divided
- Scales Smooth

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COLUBRIDAE
Tantilla
- Black headed Snakes
- Normal snout
- 15 Scale rows
- No loreal
- Anal Plate divided
- Smooth Scales
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COLUBRIDAE
Oxybelis
- Vine Snakes
- Head long and nose sharp
- Tail long and slender
- 17 Scale rows
- No loreal
- Anal Plate divided
- Smooth scales
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COLUBRIDAE
Ficimia
- Southern Hook-nosed Snakes
- Rostral relatively large, separating prefrontals and in contact with frontal
- Head Shorter, rostral acute and turned up at tip
- Tail short and thick
- 17 Scale rows
- No loreal
- Anal Plate divided
- Smooth scales
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COLUBRIDAE
Gyalopion
- Desert Hooknose Snakes
- Rostral Smaller, separating small internasals and in contact with prefrontals
- Head Shorter, rostral acute and turned up at tip
- Tail short and thick
- 17 Scale rows
- No loreal
- Anal Plate divided
- Smooth scales

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COLUBRIDAE
Elaphe
- Fox, Rat, Corn Snakes
- 25 or more scale rows
- Rounded Pupil
- 1 or more preoculars
- 2 postoculars
- 2 internasals
- Loreal
- Anal plate divided
- Smooth/Weakly keeled Scales
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COLUBRIDAE
Coniophanes
- Black striped Snakes
- 19 scale rows
- Rounded pupil
- 1 or more preoculars
- Anal plate divided
- Smooth Scales
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COLUBRIDAE
Hypsiglema
- Night Snakes
- Dorsal pattern consists of small blothces or 1 or 2 series of smaller alternating spots on sides
- 1 loreal
- 2 postoculars
- 1 anterior temporal
- 7-8 upper labials
- Elliptical pupil
- 1 or more preopticals
- 19 or more scale rows
- Anal plate divided
- All scales smooth
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COLUBRIDAE
Leptodeira
- Cat-Eyed SnakesDorsal Pattern of 22-26 large blotchs with no alternating lateral spots
- 1 loreal
- 2 postoculars
- 1 anterior temporal
- 7-8 upper labials
- Elliptical pupil
- 1 or more preopticals
- 19 or more scale rows
- Anal plate divided
- All scales smooth
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COLUBRIDAE
Farancia
- Rainbow/Mud Snakes
- Stripes?
- 7 upper labials
- 8-10 lower labials
- 1 internasals
- No preocular
- ventrals more than 160
- Loreal
- 19-21 scale rows
- Anal Plate divided
- Smooth scales
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COLUBRIDAE
Trimorphodon
- Lyre Snakes
- No suboculars
- Elliptical Pupils
- All or most caudals divided
- Anal Plate not divided
- Scales smooth

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COLUBRIDAE
Phyllorhynchus
- Leaf-nosed snakes
- Suboculars present
- Elliptical Pupil
- Rostral very large with free lateral edges
- Fewer than 27 scale rows
- 2 prefrontals
- All or most caudals divided
- Anal plate not divided
- Smooth/keeled Scales
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