Field guide · Species directory
Reptiles
Alabama Red-bellied Turtle
Pseudemys alabamensis
A medium turtle endemic to the Mobile Bay drainage of Alabama. Federally endangered. Distinguished from other red-bellied turtles by Alabama…
Alligator Snapping Turtle
Macrochelys temminckii
The largest freshwater turtle in North America — record specimens over 200 pounds and 100+ years old. A prehistoric-looking ambush predator …
American Alligator
Alligator mississippiensis
A keystone species and conservation success — recovered from endangered status in 1987 and now numbers over a million in Louisiana alone.
American Crocodile
Crocodylus acutus
The shyer, narrower-snouted cousin of the alligator — and one of only two places on Earth (south Florida) where alligators and crocodiles co…
Blanding's Turtle
Emydoidea blandingii
A medium turtle with a distinctive bright yellow chin and throat and a high-domed black shell with yellow spotting. Among the slowest-maturi…
Bog Turtle
Glyptemys muhlenbergii
North America's smallest turtle — adults barely reach 4 inches. Their bright yellow neck patches are unmistakable. Critically endangered due…
Desert Tortoise
Gopherus agassizii
A long-lived (60–80 year) keystone tortoise of the Mojave whose burrows shelter dozens of other species. Populations have declined 90% over …
Diamondback Terrapin (Mid-Atlantic)
Malaclemys terrapin terrapin
Northeastern subspecies of diamondback terrapin. Critically declined due to crab pot bycatch.
Indigo Snake (Eastern)
Drymarchon couperi
Federally threatened. Among the longest US snakes.
Massasauga (Eastern)
Sistrurus catenatus catenatus
A small endangered rattlesnake of eastern wetland habitats. Federally listed since 2016.
Massasauga (Western)
Sistrurus tergeminus
A small federally endangered rattlesnake of the central US prairies. Recently recognized as distinct from eastern massasauga. Populations cr…
Puerto Rican Boa
Chilabothrus inornatus
A medium-large constrictor (up to 7 ft) endemic to Puerto Rico. Closely tied to bat caves — they're famous for catching bats in mid-flight a…
Texas Horned Lizard
Phrynosoma cornutum
Texas's state reptile and a beloved icon — popularly called "horny toads" though they're lizards. Specialized to eat almost exclusively harv…
Timber Rattlesnake
Crotalus horridus
A heavy-bodied rattlesnake with banded patterning ranging from yellow-and-black to dark phases. Among the most docile rattlesnakes — relies …
Western Pond Turtle
Actinemys marmorata
The only freshwater turtle native to most of California, Oregon, and Washington. Populations have declined dramatically due to invasive bull…
Wood Turtle
Glyptemys insculpta
A medium turtle with a sculpted brown shell (each scute pyramidal) and orange skin. Notable as one of the more intelligent turtles — they ca…
Banded Gecko
Coleonyx variegatus
A small nocturnal gecko endemic to southwestern deserts. Among the smallest native US lizards.
Black Pine Snake
Pituophis melanoleucus lodingi
A large constrictor restricted to longleaf pine habitats.
Black Racer
Coluber constrictor priapus
A long thin black non-venomous snake. Among the fastest snakes in North America. Active predator; pursues prey at high speed.
Broad-headed Skink
Plestiodon laticeps
A medium-sized smooth-scaled lizard. Males in breeding season develop bright orange-red head. Among the larger US skinks.
California King Snake
Lampropeltis californiae
A non-venomous constrictor with bold black-and-yellow or black-and-white banding. Eats other snakes (including venomous).
Common Chuckwalla
Sauromalus ater
A large stocky herbivorous lizard — males can exceed 16 inches. When threatened, they wedge into rock cracks and inflate their lungs to anch…
Common Five-lined Skink
Plestiodon fasciatus
A small smooth-scaled lizard with five pale stripes down a dark body and (in juveniles) a brilliant blue tail. The blue tail breaks off easi…
Common Garter Snake
Thamnophis sirtalis
The classic backyard snake — non-venomous, mostly harmless, and one of the few reptile species that survives the brutal cold of subarctic Al…
Common Side-blotched Lizard
Uta stansburiana
A small abundant western lizard with a dark blotch behind each foreleg. Among the most ecologically important small reptiles of western dese…
Common Snapping Turtle
Chelydra serpentina
A heavyweight prehistoric-looking turtle with a powerful beak and a 50-pound max weight. Long-lived (up to 100 years), often-misunderstood, …
Cottonmouth
Agkistrodon piscivorus
A heavy-bodied venomous semi-aquatic snake with a white "cotton" mouth lining (displayed defensively). Often falsely called "water moccasin"…
Cuban Knight Anole
Anolis equestris
A massive anole — up to 19 inches — introduced to South Florida and now widespread. Displaces native green anoles and is occasionally seen e…
Desert Iguana
Dipsosaurus dorsalis
A pale gray-tan lizard with a rounded snout and dark-banded tail. Among the most heat-tolerant North American lizards, active at body temper…
Diamondback Terrapin
Malaclemys terrapin
A specialized salt-marsh turtle with concentric "diamond" patterns on each shell scute. Once harvested for soup to near-extinction, they rem…
Eastern Box Turtle
Terrapene carolina
Long-lived terrestrial turtles with high-domed shells and strong site fidelity — they can live 100+ years and rarely leave their home territ…
Eastern Coachwhip
Masticophis flagellum
A long fast-moving non-venomous snake — up to 8 feet — with a distinctive two-tone color: dark brown head and forequarters fading to lighter…
Eastern Collared Lizard
Crotaphytus collaris
A striking lizard with bright turquoise-blue body, yellow head, and black neck collar. Famous for sprinting on hind legs only — like a tiny …
Eastern Copperhead
Agkistrodon contortrix
A beautifully patterned venomous pit viper — tan with hourglass-shaped chestnut crossbands. Excellent camouflage on autumn leaves makes them…
Eastern Coral Snake
Micrurus fulvius
A slender venomous snake with brilliant red-yellow-black banding — neurotoxic venom that's among North America's most potent. Highly secreti…
Eastern Corn Snake
Pantherophis guttatus
A striking medium-sized snake with bright orange-red blotches outlined in black on an orange-tan background. Excellent climbers that hunt ro…
Eastern Diamondback Rattlesnake
Crotalus adamanteus
The largest venomous snake in North America — adults reach 5–6 feet, with records over 8 feet. A specialist of fire-maintained pine ecosyste…
Eastern Fence Lizard
Sceloporus undulatus
A small spiny lizard that's rapidly evolving longer legs and new behaviors in response to invasive fire ants — one of the fastest-documented…
Eastern Glass Lizard
Ophisaurus ventralis
A legless lizard often mistaken for a snake. Distinguished by external ear openings and movable eyelids — true snakes have neither. Named fo…
Eastern Hognose Snake
Heterodon platirhinos
A non-venomous snake with one of the most theatrical defensive displays in nature: hood spreading like a cobra, hissing, and if pressed, rol…
Eastern Indigo Snake
Drymarchon couperi
North America's longest native snake at over 9 feet, with iridescent blue-black scales. They eat just about everything including other venom…
Eastern King Snake
Lampropeltis getula
Nicknamed the "king" because they eat other snakes — including venomous copperheads, cottonmouths, and rattlesnakes. They're immune to North…
Eastern Massasauga
Sistrurus catenatus
A small, secretive prairie rattlesnake federally Threatened in the US. Critical for wetland ecosystems but persecuted by myth — most people …
Eastern Milk Snake
Lampropeltis triangulum triangulum
A medium-sized non-venomous snake with striking red, black, and white banding — often killed in mistaken belief it's a coral snake (no coral…
Eastern Mud Turtle
Kinosternon subrubrum
A small dark-brown turtle with a smooth domed shell — often mistakenly considered a "baby snapping turtle" by people who find them crossing …
Eastern Musk Turtle
Sternotherus odoratus
A small dark turtle with a high-domed shell and two pale stripes on the head. Called "stinkpot" for the foul-smelling musk they emit when ha…
Eastern Rat Snake
Pantherophis alleghaniensis
A large non-venomous constrictor that can reach 6 feet — one of the most beneficial snakes a homeowner can have. They consume large numbers …
Eastern Ribbon Snake
Thamnophis sauritus
A slender garter-snake relative with three yellow stripes on a dark body and very long tail. Excellent swimmers, often hunting frogs and tad…
Eastern Rough Greensnake
Opheodrys aestivus
A slender bright green non-venomous snake. Eats almost exclusively caterpillars and spiders. Camouflaged perfectly against foliage.
Eastern Smooth Green Snake
Opheodrys vernalis
A small green snake found in open habitats.
Eastern Spiny Softshell
Apalone spinifera spinifera
An unusual turtle with a leathery, pancake-flat shell instead of hard scutes. Excellent swimmers with a long snorkel-like nose for breathing…
Florida Pine Snake
Pituophis melanoleucus mugitus
A non-venomous constrictor restricted to Florida pine flatwoods.
Gila Monster
Heloderma suspectum
One of only two venomous lizards in the world (the other is its Mexican cousin). Slow-moving, distinctively beaded, they spend 95% of their …
Glossy Snake
Arizona elegans
A small non-venomous snake of southwestern deserts.
Gopher Tortoise
Gopherus polyphemus
A keystone species: their burrows up to 40 feet long shelter over 350 other species including snakes, frogs, mice, and burrowing owls.
Gray Rat Snake
Pantherophis spiloides
A medium-large constrictor with gray background and darker blotches. Excellent climber. Often found in barns and attics hunting rodents.
Green Anole
Anolis carolinensis
The "American chameleon" — the only anole native to the US, capable of changing from bright green to brown based on temperature, mood, and s…
Green Iguana (invasive)
Iguana iguana
A large lizard introduced to South Florida via the pet trade. Now reproducing in the wild; spreading rapidly. Major damage to native plants …
Long-nosed Snake
Rhinocheilus lecontei
A medium snake with distinctive long pointed snout.
Lyre Snake
Trimorphodon lambda
A medium colubrid snake with distinctive face markings.
Mojave Rattlesnake
Crotalus scutulatus
A medium-sized rattlesnake similar to western diamondback but with greener tones. Among the most venomous North American snakes — venom cont…
Mojave Whipsnake
Coluber lateralis
A non-venomous snake of Mojave Desert habitats.
Mud Snake
Farancia abacura
A medium-large non-venomous snake with distinctive black-and-red coloration. Specializes on giant siren salamanders.
New Mexico Whiptail
Aspidoscelis neomexicanus
A medium-sized whip-tailed lizard with 7 cream stripes on a dark background. Remarkably, every individual is female — the species reproduces…
Nightsnake
Hypsiglena torquata
A small nocturnal snake.
Northern Alligator Lizard
Elgaria coerulea
A slender brown lizard with a long tail and small legs that walks with a sinuous, almost serpentine motion. Common in Pacific Northwest gard…
Northern Pine Snake
Pituophis melanoleucus
A large non-venomous constrictor with bold black-on-white pattern. Known for fierce defensive displays (loud hissing, head-shaking, false st…
Northern Red-bellied Turtle
Pseudemys rubriventris
A medium turtle with reddish belly and dark olive shell. Northeastern populations isolated; some genetically distinct.
Northern Water Snake
Nerodia sipedon
A non-venomous water snake constantly mistaken for the venomous cottonmouth (water moccasin) — and consequently killed by frightened fisherm…
Northern Watersnake
Nerodia sipedon
A heavy-bodied non-venomous water snake often killed by people who mistake it for a cottonmouth (which doesn't occur in most of its range). …
Painted Turtle
Chrysemys picta
Bright red-and-yellow markings on the shell edges and limbs. Painted turtles are the only North American turtle that survives freezing — hat…
Peninsula Cooter
Pseudemys peninsularis
A medium turtle endemic to Florida peninsula. Distinguished from related species by orange and yellow leg markings.
Queen Snake
Regina septemvittata
A slender olive-brown semi-aquatic snake found around clean cool streams. Their diet is almost entirely freshly-molted soft-shell crayfish —…
Ringneck Snake
Diadophis punctatus
A small secretive non-venomous snake with distinctive yellow ring around neck.
Rosy Boa
Lichanura trivirgata
A docile small boa (up to 4 ft) of southwestern deserts. Three pinkish or orange stripes on a lighter background. Among the only native US b…
Rough Green Snake
Opheodrys aestivus
A slender, vivid bright-green snake that hunts insects and spiders in tree branches and shrubs. Completely harmless and so reluctant to bite…
Saltmarsh Snake
Nerodia clarkii
A small non-venomous snake adapted to saltwater habitats — among very few snakes that can tolerate seawater. Variable striped or banded patt…
Sidewinder Rattlesnake
Crotalus cerastes
A small desert rattlesnake that moves in a unique sideways "sidewinding" motion. Body makes an S-curve while only two points touch the groun…
Slender Glass Lizard
Ophisaurus attenuatus
A legless lizard often mistaken for a snake. Distinguished by ear openings and movable eyelids (snakes have neither). Brittle tail can shatt…
Sonora Whipsnake
Coluber bilineatus
A non-venomous snake of southwestern habitats.
Spectacled Caiman (invasive)
Caiman crocodilus
A small crocodilian introduced to South Florida via the pet trade. Established invasive populations in some areas.
Spotted Turtle
Clemmys guttata
A small (4-inch) turtle covered in vivid yellow polka-dots on a black shell. One of North America's most threatened turtles — illegal collec…
Texas Spiny Lizard
Sceloporus olivaceus
A medium-sized scaly lizard often seen on tree trunks and fence posts across central Texas. Males do push-up displays to defend territory.
Texas Threadsnake
Rena dulcis
Tiny fossorial snake that looks more like a shiny earthworm than a snake. About 6 inches long; eats ant larvae and termites.
Tiger Rattlesnake
Crotalus tigris
A small rattlesnake with distinctive tiger-stripe pattern. Restricted to Sonoran Desert habitats.
Vine Snake
Oxybelis aeneus
An extremely long, slender arboreal snake.
Western Diamondback Rattlesnake
Crotalus atrox
A large gray-brown rattlesnake with bold diamond patterns and a black-and-white "raccoon tail." One of the most common rattlesnakes of the d…
Western Garter Snake
Thamnophis elegans
A medium-sized garter snake. Highly variable in coloration across range.
Western Patch-nosed Snake
Salvadora hexalepis
A small snake with distinctive snout pattern.
Western Rattlesnake (Northern Pacific)
Crotalus oreganus
A widespread Western pit viper. Like all rattlesnakes, they play a critical ecological role controlling rodent populations — and they're NOT…
Western Shovel-nosed Snake
Sonora occipitalis
A small nocturnal snake with cream and reddish bands. "Swims" through loose sand using shovel-like snout.
Western Skink
Plestiodon skiltonianus
A medium-sized smooth-scaled lizard with longitudinal stripes and a brilliant blue tail in juveniles. Among the most colorful North American…
Worm Snake
Carphophis amoenus
A tiny non-venomous snake. Often mistaken for an earthworm.
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