- Adelophis - Mountain Meadow Snakes
- Adelophis copei - Cope's Mountain Meadow Snake
- Adelophis foxi - Fox's Mountain Meadow Snake
- Adelphicos - Middle American Earth Snakes
- Adelphicos latifasciatum - Oaxacan Burrowing Snake
- Adelphicos nigrilatum - Burrowing Snake
- Adelphicos quadrivirgatum - Middle American Earth Snake
- A. q. newmanorum - Newman's Earth Snake
- A. q. quadrivirgatum - Jan's Earth Snake
- Adelphicos sargii - Sargi's Earth Snake
- Adelphicos visoninus - Cope's Earth Snake
- Agkistrodon - American Moccasins
- Agkistrodon bilineatus - Cantil
- A. b. bilineatus - Mexican Cantil
- A. b. lemosespinali - Lemos-Espinal's Cantil
- A. b. russeolus - Yucatecan Cantil
- Agkistrodon contortrix - Copperhead
- A. c. contortrix - Southern Copperhead
- A. c. laticinctus - Broad-banded Copperhead
- A. c. mokasen - Northern Copperhead
- A. c. phaeogaster - Osage Copperhead
- A. c. pictigaster - Trans-Pecos Copperhead
- Agkistrodon piscivorus - Cottonmouth
- A. p. conanti - Florida Cottonmouth
- A. p. leucostoma - Western Cottonmouth
- A. p. piscivorus - Eastern Cottonmouth
- Agkistrodon taylori - Taylor's Cantil
- Agkistrodon bilineatus - Cantil
- Amastridium - Rusty-headed Snakes
- Amastridium sapperi - Rusty-headed Snake
- Arizona - Glossy Snakes
- Arizona elegans - Glossy Snake
- A. e. arenicola - Texas Glossy Snake
- A. e. candida - Mojave Glossy Snake
- A. e. eburnata - Desert Glossy Snake
- A. e. elegans - Kansas Glossy Snake
- A. e. expolita - Chihuahuan Glossy Snake
- A. e. noctivaga - Arizona Glossy Snake
- A. e. occidentalis - California Glossy Snake
- A. e. philipi - Painted Desert Glossy Snake
- Arizona pacata - Peninsular Glossy Snake
- Arizona elegans - Glossy Snake
- Atropoides - Jumping Pitvipers
- Atropoides mexicanus - Mexican Jumping Pitviper
- Atropoides nummifer - Jumping Pitviper
- Atropoides occiduus - Western Jumping Pitviper
- Atropoides olmec - Olmecan Jumping Pitviper
- Boa - Boas
- Boa constrictor - Boa Constrictor
- B. c. imperator - Mexican Boa Constrictor
- Boa constrictor - Boa Constrictor
- Bogertophis - Desert Rat Snakes
- Bogertophis rosaliae - Baja California Rat Snake
- Bogertophis subocularis - Trans-Pecos Rat Snake
- B. s. amplinotus - Southern Trans-Pecos Rat Snake
- B. s. subocularis - Northern Trans-Pecos Rat Snake
- Bothriechis - Palm-pitvipers
- Bothriechis aurifer - Yellow-blotched Palm-pitviper
- Bothriechis bicolor - Guatemalan Palm-pitviper
- Bothriechis rowleyi - Rowley's Palm-pitviper
- Bothriechis schlegeli - Eyelash Palm-pitviper
- Bothrops - Lanceheads
- Bothrops asper - Terciopelo
- Carphophis - North American Wormsnakes
- Carphophis amoenus - Eastern Wormsnake
- C. a. amoenus - Eastern Wormsnake
- C. a. helenae - Midwestern Wormsnake
- Carphophis vermis - Western Wormsnake
- Carphophis amoenus - Eastern Wormsnake
- Cemophora - Scarletsnakes
- Cemophora coccinea - Scarletsnake
- C. c. coccinea - Florida Scarletsnake
- C. c. copei - Northern Scarletsnake
- C. c. lineri - Texas Scarletsnake
- Cemophora coccinea - Scarletsnake
- Cerrophidion - Montane Pitvipers
- Cerrophidion barbouri - Borbour's Montane Pitviper
- Cerrophidion godmani - Godman's Montane Pitviper
- Cerrophidion petlalcalensis - Cerro Petlalcala Montane Viper
- Cerrophidion tzotzilorum - Tzotzils Montane Pitviper
- Charina - Rubber Boas
- Charina bottae - Northern Rubber Boa
- Charina umbratica - Southern Rubber Boa
- Chersodromus - Earth Runners
- Chersodromus liebmanni - Liebmann's Earth Runner
- Chersodromus rubriventris - Red-bellied Earth Runner
- Chilomeniscus - Sandsnakes
- Chilomeniscus savagei - Cerralvo Island Sandsnake
- Chilomeniscus stramineus - Variable Sandsnake
- Chionactis - Shovel-nosed Snakes
- Chionactis occipitalis - Western Shovel-nosed Snake
- C. o. annulata - Colorado Desert Shovel-nosed Snake
- C. o. klauberi - Tucson Shovel-nosed Snake
- C. o. occipitalis - Mojave Shovel-nosed Snake
- C. o. talpina - Nevada Shovel-nosed Snake
- Chionactis palarostris - Sonoran Shovel-nosed Snake
- C. p. organica - Organ Pipe Shovel-nosed Snake
- C. p. palarostris - Sonoran Shovel-nosed Snake
- Chionactis occipitalis - Western Shovel-nosed Snake
- Clelia - Mussuranas
- Clelia scytalina - Mexican Snake Eater
- Clonophis - Kirtland's Snakes
- Clonophis kirtlandii - Kirtland's Snake
- Coluber - North American Racers, Coachwhips, And Whipsnakes
- Coluber anthonyi - Clarion Island Whipsnake
- Coluber aurigulus - Cape Striped Whipsnake
- Coluber barbouri - Espiritu Santo Striped Whipsnake
- Coluber bilineatus - Sonoran Whipsnake
- Coluber constrictor - North American Racer
- C. c. anthicus - Buttermilk Racer
- C. c. constrictor - Northern Black Racer
- C. c. etheridgei - Tan Racer
- C. c. flaviventris - Eastern Yellow-bellied Racer
- C. c. foxii - Blue Racer
- C. c. helvigularis - Brown-chinned Racer
- C. c. latrunculus - Black-masked Racer
- C. c. mormon - Western Yellow-bellied Racer
- C. c. oaxaca - Mexican Racer
- C. c. paludicola - Everglades Racer
- C. c. priapus - Southern Black Racer
- Coluber flagellum - Coachwhip
- C. f. cingulum - Sonoran Coachwhip
- C. f. flagellum - Eastern Coachwhip
- C. f. lineatulus - Lined Coachwhip
- C. f. piceus - Red Racer
- C. f. ruddocki - San Joaquin Coachwhip
- C. f. testaceus - Western Coachwhip
- Coluber fuliginosus - Baja California Coachwhip
- Coluber lateralis - Striped Racer
- C. l. euryxanthus - Alameda Striped Racer
- C. l. lateralis - California Striped Racer
- Coluber mentovarius - Neotropical Whipsnake
- C. m. mentovarius - Neotropical Whipsnake
- C. m. striolatus - Mexican Whipsnake
- C. m. variolosus - Tres Marias Whipsnake
- Coluber schotti - Schott's Whipsnake
- C. s. ruthveni - Ruthven's Whipsnake
- C. s. schotti - Schott's Whipsnake
- Coluber slevini - San Esteban Island Whipsnake
- Coluber taeniatus - Striped Whipsnake
- C. t. girardi - Central Texas Whipsnake
- C. t. taeniatus - Desert Striped Whipsnake
- Coniophanes - Black-striped Snakes
- Coniophanes alvarezi - Chiapan Stripeless Snake
- Coniophanes bipunctatus - Mottled-jaw Spot-bellied Snake
- C. b. bipunctatus - Two-spotted Snake
- C. b. biseriatus - Smith's Two-spotted Snake
- Coniophanes fissidens - Yellow-bellied Snake
- C. f. convergens - Veracruz Yellow-bellied Snake
- C. f. dispersus - Smith's Yellow-bellied Snake
- C. f. fissidens - White-lipped Spot-bellied Snake
- C. f. proterops - Cope's Yellow-bellied Snake
- C. f. punctigularis - Spot-throated Lizard Eater
- Coniophanes imperialis - Regal Black-striped Snake
- C. i. clavatus - Black-striped Snake
- C. i. copei - Cope's Black-striped Snake
- C. i. imperialis - Tamaulipan Black-striped Snake
- Coniophanes lateritius - Stripeless Snake
- Coniophanes melanocephalus - Blackhead Stripeless Snake
- Coniophanes meridanus - Peninsular Stripeless Snake
- Coniophanes piceivittis - Cope's Black-striped Snake
- C. p. frangivirgatus - Peter's Black-striped Snake
- C. p. piceivittis - Cope's Black-striped Snake
- C. p. taylori - Taylor's Black-striped Snake
- Coniophanes quinquevittatus - Five-striped Snake
- Coniophanes sarae - Sara's Stripeless Snake
- Coniophanes schmidti - Schmidt's Black-striped Snake
- Conophis - Road Guarders
- Conophis concolor - Peninsular Road Guarder
- Conophis lineatus - Central American Road Guarder
- C. l. dunni - Dunn's Road Guarder
- C. l. lineatus - Lined Road Guarder
- Conophis morai - Tuxtlan Road Guarder
- Conophis pulcher - Beautiful Road Guarder
- Conophis vittatus - Striped Road Guarder
- Conopsis - Mexican Earth Snakes
- Conopsis acutus - Spotted Tolucan Earthsnake
- Conopsis amphistricha - Twin-spotted Mexican Earthsnake
- Conopsis biserialis - Two-lined Mexican Earthsnake
- Conopsis lineatus - Lined Tolucan Earthsnake
- C. l. lineatus - Lined Tolucan Earthsnake
- C. l. varians - Lineless Tolucan Earthsnake
- C. l. wetmorei - Wetmore's Tolucan Earthsnake
- Conopsis megalodon - Carlos San Felipe Earthsnake
- Conopsis nasus - Large-nosed Earthsnake
- C. n. labialis - Chihuahuan Earthsnake
- C. n. nasus - Plateau Mexican Earthsnake
- Contia - Sharp-tailed Snakes
- Contia longicaudae - Forest Sharp-tailed Snake
- Contia tenuis - Sharp-tailed Snake
- Crotalus - Rattlesnakes
- Crotalus adamanteus - Eastern Diamond-backed Rattlesnake
- Crotalus angelensis - Angel Island Rattlesnake
- Crotalus aquilus - Queretaran Dusky Rattlesnake
- Crotalus atrox - Western Diamond-backed Rattlesnake
- Crotalus basiliscus - Mexican West Coast Rattlesnake
- Crotalus caliginis - Coronado Island Rattlesnake
- Crotalus catalinensis - Santa Catalina Island Rattlesnake
- Crotalus cerastes - Sidewinder
- C. c. cerastes - Mojave Desert Sidewinder
- C. c. cercobombus - Sonoran Sidewinder
- C. c. laterorepens - Colorado Desert Sidewinder
- Crotalus cerberus - Arizona Black Rattlesnake
- Crotalus enyo - Baja California Rattlesnake
- C. e. cerralvensis - Cerralvo Island Rattlesnake
- C. e. enyo - Lower California Rattlesnake
- C. e. furvus - Rosario Rattlesnake
- Crotalus ericsmithi - Guerreran Long-Tailed Rattlesnake
- Crotalus estebanensis - Isla San Esteban Black-tailed Rattlesnake
- Crotalus horridus - Timber Rattlesnake
- Crotalus intermedius - Mexican Small-headed Rattlesnake
- C. i. gloydi - Oaxacan Small-headed Rattlesnake
- C. i. intermedius - Totalcan Small-headed Rattlesnake
- C. i. omiltemanus - Omilteme Small-headed Rattlesnake
- Crotalus lannomi - Autlan Rattlesnake
- Crotalus lepidus - Rock Rattlesnake
- C. l. klauberi - Banded Rock Rattlesnake
- C. l. lepidus - Mottled Rock Rattlesnake
- C. l. maculosus - Durango Rock Rattlesnake
- C. l. morulus - Tamaulipan Rock Rattlesnake
- Crotalus lorenzoensis - San Lorenzo Island Diamond Rattlesnake
- Crotalus mitchellii - Speckled Rattlesnake
- C. m. mitchellii - San Lucan Speckled Rattlesnake
- C. m. pyrrhus - Southwestern Speckled Rattlesnake
- Crotalus molossus - Black-tailed Rattlesnake
- C. m. molossus - Northern Black-tailed Rattlesnake
- C. m. nigrescens - Mexican Black-tailed Rattlesnake
- C. m. oaxacus - Oaxacan Black-tailed Rattlesnake
- Crotalus muertensis - El Muerto Island Rattlesnake
- Crotalus oreganus - Western Rattlesnake
- C. o. abyssus - Grand Canyon Rattlesnake
- C. o. concolor - Midget Faded Rattlesnake
- C. o. helleri - Southern Pacific Rattlesnake
- C. o. lutosus - Great Basin Rattlesnake
- C. o. oreganus - Northern Pacific Rattlesnake
- Crotalus polystictus - Mexican Lancehead Rattlesnake
- Crotalus pricei - Twin-spotted Rattlesnake
- C. p. miquihuanus - Eastern Twin-spottd Rattlesnake
- C. p. pricei - Western Twin-spotted Rattlesnake
- Crotalus pusillus - Tancitaran Dusky Rattlesnake
- Crotalus ravus - Mexican Pygmy Rattlesnake
- C. r. brunneus - Oaxacan Pygmy Rattlesnake
- C. r. exiguous - Guerreran Pygmy Rattlesnake
- C. r. ravus - Mexican Massasauga
- Crotalus ruber - Red Diamond Rattlesnake
- Crotalus scutulatus - Mohave Rattlesnake
- C. s. salvini - Salvin's Rattlesnake
- C. s. scutulatus - Mohave Rattlesnake
- Crotalus simus - Middle American Rattlesnake
- C. s. culminatus - Northwestern Middle American Rattlesnake
- C. s. tzabcan - Tzabcan Rattlesnake
- Crotalus stejnegeri - Long-tailed Rattlesnake
- Crotalus stephensi - Panamint Rattlesnake
- Crotalus tancitaiensis - Tancítaro Rattlesnake
- Crotalus tigris - Tiger Rattlesnake
- Crotalus tortugensis - Tortuga Island Diamond-backed Rattlesnake
- Crotalus totonacus - Tontonacan Rattlesnake
- Crotalus transversus - Cross-banded Mountain Rattlesnake
- Crotalus triseriatus - Mexican Dusky Rattlesnake
- C. t. armstrongi - Western Dusky Rattlesnake
- C. t. triseriatus - Mexican Dusky Rattlesnake
- Crotalus viridis - Prairie Rattlesnake
- Crotalus willardi - Ridge-nosed Rattlesnake
- C. w. amabilis - Del Nido Ridge-nosed Rattlesnake
- C. w. meridionalis - Southern Ridge-nosed Rattlesnake
- C. w. obscurus - New Mexico Ridge-nosed Rattlesnake
- C. w. silus - Chihuahuan Ridge-nosed Rattlesnake
- C. w. willardi - Arizona Ridge-nosed Rattlesnake
- Cryophis - Cloud Forrest Snakes
- Cryophis hallbergi - Hallberg's Cloud Forest Snake
- Dendrophidion - Forest Racers
- Dendrophidion vinitor - Barred Forest Racer
- Diadophis - Ring-necked Snakes
- Diadophis punctatus - Ring-necked Snake
- D. p. acricus - Key Ring-necked Snake
- D. p. amabilis - Pacific Ring-necked Snake
- D. p. anthonyi - Anthony's Ring-necked Snake
- D. p. arnyi - Prairie Ring-necked Snake
- D. p. dugesii - Dugès's Ring-necked Snake
- D. p. edwardsii - Northern Ring-necked Snake
- D. p. modestus - San Bernardino Ring-necked Snake
- D. p. occidentalis - Northwestern Ring-necked Snake
- D. p. pulchellus - Coral-bellied Ring-necked Snake
- D. p. punctatus - Southern Ring-necked Snake
- D. p. regalis - Regal Ring-necked Snake
- D. p. similis - San Diego Ring-necked Snake
- D. p. stictogenys - Mississippi Ring-necked Snake
- D. p. vandenburgii - Monterey Ring-necked Snake
- Diadophis punctatus - Ring-necked Snake
- Dipsas - Snail-eating Snakes
- Dipsas brevifacies - Snail-eating Thirst Snake
- Dipsas gaigeae - Gaige's Snail-eating Snake
- Dipsas maxillaris - Werner's Snail-eating Snake
- Drymarchon - Indigo Snakes
- Drymarchon couperi - Eastern Indigo Snake
- Drymarchon melanurus - Central American Indigo Snake
- D. m. erebennus - Texas Indigo Snake
- D. m. melanurus - Central American Indigo Snake
- D. m. orizabensis - Orizaba Cribo
- D. m. rubidus - Mexican West Coast Cribo
- D. m. unicolor - Central American Cribo
- Drymobius - Neotropical Racers
- Drymobius chloroticus - Green Highland Racer
- Drymobius margaritiferus - Speckled Racer
- D. m. fistulosus - Central American Speckled Racer
- D. m. margaritiferus - Northern Speckled Racer
- D. m. occidentalis - Western Speckled Racer
- Enulius - Middle American Longtail Snakes
- Enulius flavitorques - Pacific Longtail Snake
- E. f. sumichrasti - Sumichrast's Longtail Snake
- E. f. unicolor - Fischer's Longtail Snake
- Enulius oligostichus - Mexican Longtail Snake
- Enulius flavitorques - Pacific Longtail Snake
- Eridiphas - Baja California Night Snakes
- Eridiphas slevini - Baja California Night Snake
- Exiliboa - Mexican Dwarf Boas
- Exiliboa placata - Oaxacan Dwarf Boa
- Farancia - Mudsnakes And Rainbow Snakes
- Farancia abacura - Red-bellied Mudsnake
- F. a. abacura - Eastern Mudsnake
- F. a. reinwardtii - Western Mudsnake
- Farancia erytrogramma - Rainbow Snake
- F. e. erytrogramma - Common Rainbow Snake
- F. e. seminola - Southern Florida Rainbow Snake
- Farancia abacura - Red-bellied Mudsnake
- Ficimia - Eastern Hook-nosed Snakes
- Ficimia hardyi - Hardy's Hook-nosed Snake
- Ficimia olivaceus - Brown Hook-nosed Snake
- Ficimia publia - Blotched Hook-nosed Snake
- Ficimia ramirezi - Ramirez's Hook-nosed Snake
- Ficimia ruspator - Guerreran Hook-nosed Snake
- Ficimia streckeri - Tamaulipan Hook-nosed Snake
- Ficimia variegata - Tehuantepec Hook-nosed Snake
- Geagras - Tehuantepec Striped Snakes
- Geagras redimitus - Tehuantepec Striped Snake
- Geophis - Central American Earth Snakes
- Geophis anocularis - Sierra Mije Earth Snake
- Geophis bicolor - Mexican Plateau Earth Snake
- Geophis blanchardi - Blanchard's Earth Snake
- Geophis cancellatus - Chiapan Earth Snake
- Geophis carinosus - Keeled Earth Snake
- Geophis chalybeus - Veracruz Earth Snake
- Geophis dubius - Mesa Del Sur Earth Snake
- Geophis duellmani - Sierra Juarez Earth Snake
- Geophis dugesii - Dugès's Earth Snake
- G. d. aquilonaris - Chihuahuan Earth Snake
- G. d. dugesii - Dugès's Earth Snake
- Geophis immaculatus - Downs's Earth Snake
- Geophis incomptus - Sierra Colecoman Earth Snake
- Geophis isthmicus - Isthmian Earth Snake
- Geophis juarezi - Benito Juarez Earth Snake
- Geophis juliani - Zurtuche's Earth Snake
- Geophis laticinctus - Mesa Central Earth Snake
- Geophis laticollaris - Widecollar Earth Snake
- Geophis latifrontalis - Potosi Earth Snake
- G. l. latifrontalis - Potosi Earth Snake
- G. l. semiannulatus - Mountain Earth Snake
- Geophis maculiferus - Michoacán Earth Snake
- Geophis mutitorques - Highland Earth Snake
- Geophis nasalis - Coffee Earth Snake
- Geophis nigrocinctus - Black-banded Earth Snake
- Geophis omiltemanus - Guerreran Earth Snake
- Geophis petersii - Peter's Earth Snake
- Geophis pyburni - Pyburn's Earth Snake
- Geophis rhodogaster - Rose-bellied Earth Snake
- Geophis rostralis - Sierra Madre Earth Snake
- Geophis russatus - Red Earth Snake
- Geophis sallaei - Salle's Earth Snake
- Geophis semidoliatus - Broken-ringed Earth Snake
- Geophis sieboldi - Siebold's Earth Snake
- Geophis tarascae - Tarascan Earth Snake
- Gyalopion - Western Hook-nosed Snakes
- Gyalopion canum - Chihuahuan Hook-nosed Snake
- Gyalopion quadrangulare - Thornscrub Hook-nosed Snake
- Heterodon - North American Hog-nosed Snakes
- Heterodon gloydi - Dusty Hog-nosed Snake
- Heterodon kennerlyi - Mexican Hog-nosed Snake
- Heterodon nasicus - Plains Hog-nosed Snake
- Heterodon platirhinos - Eastern Hog-nosed Snake
- Heterodon simus - Southern Hog-nosed Snake
- Hypsiglena - North American Nightsnakes
- Hypsiglena affinis - Boulenger's Nightsnake
- Hypsiglena chlorophaea - Desert Nightsnake
- H. c. catalinae - Santa Catalina Island Nightsnake
- H. c. chlorophaea - Sonoran Nightsnake
- H. c. deserticola - Desert Nightsnake
- H. c. loreala - Mesa Verde Nightsnake
- Hypsiglena jani - Chihuahuan Nightsnake
- H. j. dunklei - Dunkle's Nightsnake
- H. j. jani - Jan's Nightsnake
- H. j. texana - Texas Nightsnake
- Hypsiglena ochrorhyncha - Coast Nightsnake
- H. o. baueri - Bauer's Nightsnake
- H. o. gularis - Isla Partida Norte Nightsnake
- H. o. klauberi - San Diego Nightsnake
- H. o. martinensis - Isla San Martin Nightsnake
- H. o. nuchalata - California Nightsnake
- H. o. ochrorhyncha - Coast Nightsnake
- H. o. unaocularis - Clarion Island Nightsnake
- H. o. venusta - Islands Nightsnake
- Hypsiglena tanzeri - Tanzer's Nightsnake
- Hypsiglena torquata - Collar Nightsnake
- Imantodes - Blunthead Tree Snakes
- Imantodes cenchoa - Blunthead Tree Snake
- I. c. leucomelas - Cope's Blunthead Tree Snake
- Imantodes gemmistratus - Central American Tree Snake
- I. g. gemmistratus - Greater Blunthead Tree Snake
- I. g. gracillimus - Slender Blunthead Tree Snake
- I. g. latistratus - Red Blunthead Tree Snake
- I. g. luciodorsus - Common Blunthead Tree Snake
- I. g. reticulatus - Reticulated Blunthead Tree Snake
- I. g. splendidus - Splendid Blunthead Tree Snake
- Imantodes tenuissimus - Yucatán Blunthead Tree Snake
- Imantodes cenchoa - Blunthead Tree Snake
- Lampropeltis - Kingsnakes & Milksnakes
- Lampropeltis alterna - Gray-banded Kingsnake
- Lampropeltis calligaster - Yellow-bellied Kingsnake
- L. c. calligaster - Prairie Kingsnake
- L. c. occipitolineata - South Florida Mole Kingsnake
- L. c. rhombomaculata - Mole Kingsnake
- Lampropeltis catalinensis - Isla Santa Catalina Kingsnake
- Lampropeltis extenuata - Short-tailed Snake
- Lampropeltis getula - Common Kingsnake
- L. g. californiae - California Kingsnake
- L. g. floridana - Florida Kingsnake
- L. g. getula - Eastern Kingsnake
- L. g. holbrooki - Speckled Kingsnake
- L. g. meansi - Apalachicola Kingsnake
- L. g. nigra - Black Kingsnake
- L. g. nigrita - Western Black Kingsnake
- L. g. splendida - Desert Kingsnake
- Lampropeltis herrerae - Todos Santos Island Kingsnake
- Lampropeltis knoblochi - Chihuahuan Mountain Kingsnake
- Lampropeltis mexicana - San Luis Potosi Kingsnake
- L. m. greeri - Greer's Mountain Kingsnake
- L. m. mexicana - San Luis Potosí Mountain Kingsnake
- L. m. thayeri - Thayer's Mountain Kingsnake
- Lampropeltis pyromelana - Sonoran Mountain Kingsnake
- L. p. infralabialis - Utah Mountain Kingsnake
- L. p. pyromelana - Arizona Mountain Kingsnake
- Lampropeltis ruthveni - Querétaro Mountain Kingsnake
- Lampropeltis triangulum - Milksnake
- L. t. abnorma - Guatemalan Milksnake
- L. t. amaura - Louisiana Milksnake
- L. t. annulata - Mexican Milksnake
- L. t. arcifera - Jalisco Milksnake
- L. t. blanchardi - Blanchard's Milksnake
- L. t. campbelli - Pueblan Milksnake
- L. t. celaenops - New Mexico Milksnake
- L. t. conanti - Conant's Milksnake
- L. t. dixoni - Dixon's Milksnake
- L. t. elapsoides - Scarlet Kingsnake
- L. t. gentilis - Central Plains Milksnake
- L. t. multistriata - Pale Milksnake
- L. t. nelsoni - Nelson's Milksnake
- L. t. oligozona - Pacific Central American Milksnake
- L. t. polyzona - Veracruz Milksnake
- L. t. sinaloae - Sinaloan Milksnake
- L. t. smithi - Smith's Milksnake
- L. t. syspila - Red Milksnake
- L. t. taylori - Utah Milksnake
- L. t. triangulum - Eastern Milksnake
- Lampropeltis zonata - California Mountain Kingsnake
- L. z. agalma - Baja California Mountain Kingsnake
- L. z. multicincta - Sierra Mountain Kingsnake
- L. z. multifasciata - Coast Mountain Kingsnake
- L. z. parvirubra - San Bernardino Mountain Kingsnake
- L. z. pulchra - San Diego Mountain Kingsnake
- L. z. zonata - St. Helena Mountain Kingsnake
- Laticauda - Banded Seasnakes
- Laticauda colubrina - Banded Seasnake
- Leptodeira - Cat-eyed Snakes
- Leptodeira annulata - Banded Cat-eyed Snake
- L. a. cussiliris - Duellman's Cat-eyed Snake
- Leptodeira frenata - Rain Forest Cat-eyed Snake
- L. f. frenata - Cope's Rain Forest Cat-eyed Snake
- L. f. malleisi - Malleis's Cat-eyed Snake
- L. f. yucatanensis - Peninsular Cat-eyed Snake
- Leptodeira maculata - Southwestern Cat-eyed Snake
- Leptodeira nigrofasciata - Black-banded Cat-eyed Snake
- Leptodeira polysticta - Small-spotted Cat-eyed Snake
- Leptodeira punctata - Western Cat-eyed Snake
- Leptodeira septentrionalis - Northern Cat-eyed Snake
- Leptodeira splendida - Splendid Cat-eyed Snake
- L. s. bressoni - Bresson's Splendid Cat-eyed Snake
- L. s. ephippiata - Saddled Cat-eyed Snake
- L. s. splendida - Günther's Splendid Cat-eyed Snake
- Leptodeira annulata - Banded Cat-eyed Snake
- Leptophis - Parrot Snakes
- Leptophis ahaetulla - Parrot Snake
- L. a. praestans - Northern Green Frogger
- Leptophis diplotropis - Pacific Coast Parrot Snake
- L. d. diplotropis - Pacific Coast Parrot Snake
- L. d. forreri - Forrer's Parrot Snake
- Leptophis mexicanus - Mexican Parrot Snake
- L. m. mexicanus - Mexican Parrot Snake
- L. m. septentrionalis - Tamaulipan Parrot Snake
- L. m. yucatanensis - Yucatecan Tree Snake
- Leptophis modestus - Cloud Forrest Parrot Snake
- Leptophis ahaetulla - Parrot Snake
- Leptotyphlops - Threadsnakes
- Leptotyphlops bressoni - Michoacán Slender Threadsnake
- Leptotyphlops dissectus - New Mexico Threadsnake
- Leptotyphlops dulcis - Texas Threadsnake
- L. d. dulcis - Texas Threadsnake
- L. d. rubellum - South Texas Threadsnake
- Leptotyphlops goudotii - Black Threadsnake
- L. g. bakewelli - Bakewell's Threadsnake
- L. g. phenops - Slender Threadsnake
- Leptotyphlops humilis - Western Threadsnake
- L. h. boettgeri - Ceralvo Island Threadsnake
- L. h. cahuilae - Desert Threadsnake
- L. h. chihuahuaensis - Chihuahuan Threadsnake
- L. h. dugesii - Mexican Threadsnake
- L. h. humilis - SouthWestern Threadsnake
- L. h. levitoni - Santa Catalina Threadsnake
- L. h. lindsayi - Lindsay's Threadsnake
- L. h. segregus - Trans-Pecos Threadsnake
- L. h. tenuiculus - Potosi Threadsnake
- L. h. utahensis - Utah Threadsnake
- Leptotyphlops maximus - Giant Threadsnake
- Leptotyphlops myopicus - Tampico Threadsnake
- L. m. iversoni - Iverson's Blindsnake
- L. m. myopicus - Tampico Threadsnake
- Lichanura - Rosy Boas
- Lichanura trivirgata - Rosy Boa
- L. t. bostici - Cedros Island Boa
- L. t. gracia - Desert Rosy Boa
- L. t. roseofusca - Coastal Rosy Boa
- L. t. saslowi - Mid-Baja Rosy Boa
- L. t. trivirgata - Mexican Rosy Boa
- Lichanura trivirgata - Rosy Boa
- Loxocemus - Mexican Burrowing Pythons
- Loxocemus bicolor - Mexican Burrowing Python
- Manolepis - Thinscaled Snakes
- Manolepis putnami - Thinscaled Snake
- Mastigodryas - Lizard Eaters
- Mastigodryas cliftoni - Clifton's Lizard Eater
- Mastigodryas dorsalis - Striped Lizard Eater
- Mastigodryas melanolomus - Common Lizard Eater
- M. m. melanolomus - Cope's Lizard Eater
- M. m. slevini - Slevin's Lizard Eater
- M. m. stuarti - Stuart's Lizard Eater
- M. m. tehuanae - Tehuana Lizard Eater
- M. m. veraecrucis - Olive Lizard Eater
- Micruroides - Sonoran Coralsnakes
- Micruroides euryxanthus - Sonoran Coralsnake
- M. e. australis - Sonora Coralsnake
- M. e. euryxanthus - Arizona Coralsnake
- M. e. neglectus - Sinaloa Coralsnake
- Micruroides euryxanthus - Sonoran Coralsnake
- Micrurus - American Coralsnakes
- Micrurus bernadi - Saddled Coralsnake
- Micrurus bogerti - Coastal Coralsnake
- Micrurus browni - Sierra Madre Coralsnake
- M. b. browni - Common Sierra Madre Coralsnake
- M. b. taylori - Acapulco Coral Snake
- Micrurus diastema - Variable Coralsnake
- M. d. affinis - Speckled Coralsnake
- M. d. alienus - Yucateca Coralsnake
- M. d. apiatus - Spotted-nose Coralsnake
- M. d. diastema - Vera Cruz Coralsnake
- M. d. macdougalli - MacDougall's Variable Coralsnake
- M. d. sapperi - Many-ringed Variable Coralsnake
- Micrurus distans - West Mexican Coralsnake
- M. d. distans - Common Clear-banded Coralsnake
- M. d. michoacanensis - Michoacán Clear-banded Coralsnake
- M. d. oliveri - Colima Clear-banded Coralsnake
- M. d. zweifeli - Zweifel's Coralsnake
- Micrurus elegans - Elegant Coralsnake
- M. e. elegans - Western Elegant Coralsnake
- M. e. veraepacis - Verapaz Elegant Coralsnake
- Micrurus epippifer - Oaxacan Coralsnake
- M. e. ephippifer - Oaxacan Coralsnake
- M. e. zapotecus - Zapotecan Coralsnake
- Micrurus fulvius - Eastern Coral Snake
- Micrurus laticollaris - Balsan Coralsnake
- M. l. laticollaris - Eastern Double-collar Coralsnake
- M. l. maculirostris - Western Double-collar Coralsnake
- Micrurus latifasciatus - Broad-ringed Coralsnake
- Micrurus limbatus - Tuxtlan Coralsnake
- M. l. limbatus - Tuxtlan Banded Coralsnake
- M. l. spilosomus - Tuxtlan Spotted Coralsnake
- Micrurus nebularis - Neblina Coralsnake
- Micrurus nigrocinctus - Central American Coralsnake
- M. n. zunilensis - Zunil Coralsnake
- Micrurus pachecogili - Pueblan Coralsnake
- Micrurus proximans - Nayarit Coralsnake
- Micrurus tener - Texas Coralsnake
- M. t. fitzingeri - Guajajuato Coralsnake
- M. t. maculatus - Tampico Coralsnake
- M. t. microgalbineus - Spotted Coralsnake
- M. t. tener - Texas Coralsnake
- Nerodia - North American Watersnakes
- Nerodia clarkii - Saltmarsh Snake
- N. c. clarkii - Gulf Saltmarsh Snake
- N. c. compressicauda - Mangrove Saltmarsh Snake
- N. c. taeniata - Atlantic Saltmarsh Snake
- Nerodia cyclopion - Mississippi Green Watersnake
- Nerodia erythrogaster - Plain-bellied Watersnake
- N. e. alta - Aguanaval Water Snake
- N. e. bogerti - Nazas Water Snake
- N. e. erythrogaster - Red-bellied Watersnake
- N. e. flavigaster - Yellow-bellied Watersnake
- N. e. neglecta - Copper-bellied Watersnake
- N. e. transversa - Blotched Watersnake
- Nerodia fasciata - Southern Watersnake
- N. f. confluens - Broad-banded Watersnake
- N. f. fasciata - Banded Watersnake
- N. f. pictiventris - Florida Watersnake
- Nerodia floridana - Florida Green Watersnake
- Nerodia harteri - Brazos Watersnake
- Nerodia paucimaculata - Concho Watersnake
- Nerodia rhombifer - Diamond-backed Watersnake
- N. r. blanchardi - Tampico Diamond-backed Watersnake
- N. r. rhombifer - Diamond-backed Watersnake
- N. r. werleri - Tabasco Diamond-backed Watersnake
- Nerodia sipedon - Northern Watersnake
- N. s. insularum - Lake Erie Watersnake
- N. s. pleuralis - Midland Watersnake
- N. s. sipedon - Northern Watersnake
- N. s. williamengelsi - Carolina Watersnake
- Nerodia taxispilota - Brown Watersnake
- Nerodia clarkii - Saltmarsh Snake
- Ninia - Coffee Snakes
- Ninia diademata - Ring-necked Coffee Snake
- N. d. diademata - Veracruz Ring-necked Coffee Snake
- N. d. labiosa - Pacific Ring-necked Coffee Snake
- N. d. nietoi - Caribbean Ring-necked Coffee Snake
- N. d. plorator - Hidalgo Ring-necked Coffee Snake
- Ninia sebae - Red-backed Coffee Snake
- N. s. morleyi - Yucatan Red-backed Coffee Snake
- N. s. punctulata - Bocourt's Red-backed Coffee Snake
- N. s. sebae - Common Red-backed Coffee Snake
- Ninia diademata - Ring-necked Coffee Snake
- Opheodrys - Greensnakes
- Opheodrys aestivus - Rough Greensnake
- O. a. aestivus - Northern Rough Greensnake
- O. a. carinatus - Florida Rough Greensnake
- O. a. majalis - Western Rough Greensnake
- Opheodrys vernalis - Smooth Greensnake
- O. v. blanchardi - Western Smooth Greensnake
- O. v. vernalis - Eastern Smooth Greensnake
- Opheodrys aestivus - Rough Greensnake
- Ophryacus - Mexican Horned Pitvipers
- Ophryacus melanurum - Blacktail Hog-nosed Pitviper
- Ophryacus undulatus - Mexican Horned Pitviper
- Oxybelis - American Vinesnakes
- Oxybelis aeneus - Brown Vinesnake
- Oxybelis fulgidus - Green Vinesnake
- Oxyrhopus - Calico False Coralsnakes
- Oxyrhopus petola - Calico False Coralsnake
- O. p. sebae - Seba's False Coralsnake
- Oxyrhopus petola - Calico False Coralsnake
- Pantherophis - North American Ratsnakes
- Pantherophis bairdi - Baird's Ratsnake
- Pantherophis emoryi - Great Plains Ratsnake
- Pantherophis gloydi - Eastern Foxsnake
- Pantherophis guttatus - Red Cornsnake
- Pantherophis obsoletus - Black Ratsnake
- P. o. lindheimeri - Texas Ratsnake
- P. o. obsoletus - Black Ratsnake
- P. o. quadrivittatus - Yellow Ratsnake
- P. o. rosalleni - Everglades Ratsnake
- P. o. spiloides - Gray Ratsnake
- Pantherophis slowinskii - Slowinski's Cornsnake
- Pantherophis vulpinus - Western Foxsnake
- Pelamis - Yellow-bellied Sea Snakes
- Pelamis platurus - Yellow-bellied Sea Snake
- Phyllorhynchus - Leaf-nosed Snakes
- Phyllorhynchus browni - Saddled Leaf-nosed Snake
- Phyllorhynchus decurtatus - Spotted Leaf-nosed Snake
- Pituophis - Bullsnakes, Pinesnakes, & Gopher Snakes
- Pituophis catenifer - Gopher Snake
- P. c. affinis - Sonoran Gopher Snake
- P. c. annectens - San Diego Gopher Snake
- P. c. bimaris - Baja California Gophersnake
- P. c. catenifer - Pacific Gopher Snake
- P. c. coronalis - Coronado Island Gophersnake
- P. c. deserticola - Great Basin Gopher Snake
- P. c. fulginatus - San Martin Gophersnake
- P. c. insulanus - Cedros Island Gopher Snake
- P. c. pumilus - Santa Cruz Gopher Snake
- P. c. sayi - Bullsnake
- Pituophis deppei - Mexican Bullsnake
- P. d. deppei - Mexican Bullsnake
- P. d. jani - Northern Mexican Bullsnake
- Pituophis lineaticollis - Middle American Gopher Snake
- P. l. gibsoni - Gibson's Gopher Snake
- P. l. lineaticollis - Cope's Gopher Snake
- Pituophis melanoleucus - Pinesnake
- P. m. lodingi - Black Pinesnake
- P. m. melanoleucus - Northern Pinesnake
- P. m. mugitus - Florida Pinesnake
- Pituophis ruthveni - Louisiana Pinesnake
- Pituophis vertebralis - San Lucan Gopher Snake
- Pituophis catenifer - Gopher Snake
- Pliocercus - False Coralsnakes
- Pliocercus andrewsi - Andrew's False Coralsnake
- Pliocercus bicolor - Northern False Coralsnake
- P. b. bicolor - Northern False Coralsnake
- P. b. hobartsmithi - Plateau False Coralsnake
- Pliocercus elapsoides - Variegated False Coralsnake
- P. e. aequalis - Salvin's False Coralsnake
- P. e. diastema - Bocourt's False Coralsnake
- P. e. elapsoides - Deppe's False Coralsnake
- P. e. occidentalis - MacDougall's False Coralsnake
- P. e. wilmarai - Mara's False Coralsnake
- Porthidium - Hog-nosed Pitvipers
- Porthidium dunni - Dunn's Hog-nosed Viper
- Porthidium hespere - Western Hog-nosed Pitviper
- Porthidium nasutum - Rainforest Hog-nosed Pitviper
- Porthidium yucatanicum - Yucatán Hog-nosed Pitviper
- Procinura - File-tailed Snakes
- Procinura aemula - File-tailed Ground Snake
- Pseudoelaphe - Tropical Ratsnakes
- Pseudoelaphe flavirufa - Tropical Ratsnake
- P. f. flavirufa - Northern Tropical Ratsnake
- P. f. matudai - Matuda's Ratsnake
- P. f. pardalina - Central American Tropical Ratsnake
- Pseudoelaphe phascens - Yucatán Ratsnake
- Pseudoelaphe flavirufa - Tropical Ratsnake
- Pseudoficimia - False Ficimias
- Pseudoficimia frontalis - False Ficimia
- Pseudoleptodeira - False Cat-eyed Snakes
- Pseudoleptodeira latifasciata - False Cat-eyed Snake
- Pseudoleptodeira uribei - Uribe's False Cat-eyed Snake
- Pseustes - Bird Snakes
- Pseustes poecilonotus - Puffing Snake
- P. p. argus - Arboreal Puffing Snake
- P. p. poecilonotus - Puffing Snake
- Pseustes poecilonotus - Puffing Snake
- Python - Pythons
- Python molurus - Indian Python
- P. m. bivittatus - Burmese Python
- Python molurus - Indian Python
- Ramphotyphlops - Australasian Blindsnakes
- Ramphotyphlops braminus - Brahminy Blindsnake
- Regina - Crayfish Snakes
- Regina alleni - Striped Crayfish Snake
- Regina grahamii - Graham's Crayfish Snake
- Regina rigida - Glossy Crayfish Snake
- R. r. deltae - Delta Crayfish Snake
- R. r. rigida - Glossy Crayfish Snake
- R. r. sinicola - Gulf Crayfish Snake
- Regina septemvittata - Queensnake
- Rhadinaea - Littersnakes
- Rhadinaea bogertorum - Oaxacan Graceful Brownsnake
- Rhadinaea cuneata - Veracruz Graceful Brownsnake
- Rhadinaea decorata - Striped Forest Snake
- Rhadinaea flavilata - Pine Woods Littersnake
- Rhadinaea forbesi - Forbes's Graceful Brownsnake
- Rhadinaea fulvivittis - Ribbon Graceful Brownsnake
- Rhadinaea gaigeae - Gaige's Pine Forest Snake
- Rhadinaea godmani - Godman's Graceful Brownsnake
- Rhadinaea hannsteini - Hannstein's Spotted-lipped Snake
- Rhadinaea hesperia - Western Graceful Brownsnake
- Rhadinaea kanalchutchan - Kanalchutchan Graceful Brownsnake
- Rhadinaea lachrymans - Tearful Pine-Oak Snake
- Rhadinaea laureata - Crowned Graceful Brownsnake
- Rhadinaea macdougalli - MacDougall's Graceful Brownsnake
- Rhadinaea marcellae - Marcella's Graceful Brownsnake
- Rhadinaea montana - Nuevo Leon Graceful Brownsnake
- Rhadinaea myersi - Myers's Graceful Brownsnake
- Rhadinaea omiltemana - Guerreran Pine Woods Snake
- Rhadinaea posadai - Posada's Graceful Brownsnake
- Rhadinaea quinquelineata - Pueblan Graceful Brownsnake
- Rhadinaea schistosa - Broken Collar Graceful Brownsnake
- Rhadinaea taeniata - Pine-Oak Snake
- R. t. aemula - Mimic Pine-Oak Snake
- R. t. taeniata - Giant Pine-Oak Snake
- Rhadinophanes - Graceful Mountain Snakes
- Rhadinophanes monticola - Graceful Mountain Snake
- Rhinocheilus - Long-nosed Snakes
- Rhinocheilus etheridgei - Isla Cerralvo Long-nosed Snake
- Rhinocheilus lecontei - Western Long-nosed Snake
- Salvadora - Patch-nosed Snakes
- Salvadora bairdi - Baird's Patch-nosed Snake
- Salvadora grahamiae - Mountain Patch-nosed Snake
- S. g. grahamiae - Mountain Patch-nosed Snake
- S. g. lineata - Texas Patch-nosed Snake
- Salvadora hexalepis - Western Patch-nosed Snake
- S. h. deserticola - Big Bend Patch-nosed Snake
- S. h. hexalepis - Desert Patch-nosed Snake
- S. h. klauberi - Baja California Patch-nosed Snake
- S. h. mojavensis - Mojave Patch-nosed Snake
- S. h. virgultea - Coast Patch-nosed Snake
- Salvadora intermedia - Oaxacan Patch-nosed Snake
- Salvadora lemniscata - Pacific Patch-nosed Snake
- Salvadora mexicana - Mexican Patch-nosed Snake
- Scaphiodontophis - Shovel-toothed Snakes
- Scaphiodontophis annulatus - Guatemalan Neck-banded Snake
- Seminatrix - Black Swampsnakes
- Seminatrix pygaea - Black Swampsnake
- S. p. cyclas - South Florida Swampsnake
- S. p. paludis - Carolina Swampsnake
- S. p. pygaea - North Florida Swampsnake
- Seminatrix pygaea - Black Swampsnake
- Senticolis - Green Ratsnakes
- Senticolis triaspis - Green Ratsnake
- S. t. intermedia - Green Ratsnake
- S. t. triaspis - Yucatec Green Ratsnake
- Senticolis triaspis - Green Ratsnake
- Sibon - Middle American Snail-eating Snakes
- Sibon dimidiata - Slender Snail Sucker
- S. d. dimidiata - Slender Snail Sucker
- S. d. grandoculis - Chipan Slender Snail Sucker
- Sibon linearis - Lined Snail Sucker
- Sibon nebulata - Cloudy Snail Sucker
- S. n. nebulata - Speckled Snail Sucker
- Sibon sanniola - Pigmy Snail Sucker
- S. s. sanniola - Pigmy Snail Sucker
- Sibon dimidiata - Slender Snail Sucker
- Sistrurus - Pigmy Rattlesnakes And Massasaugas
- Sistrurus catenatus - Massasauga
- S. c. catenatus - Eastern Massasauga
- S. c. edwardsii - Desert Massasauga
- S. c. tergeminus - Western Massasauga
- Sistrurus miliarius - Pigmy Rattlesnake
- S. m. barbouri - Dusky Pigmy Rattlesnake
- S. m. miliarius - Carolina Pigmy Rattlesnake
- S. m. streckeri - Western Pigmy Rattlesnake
- Sistrurus catenatus - Massasauga
- Sonora - North American Groundsnakes
- Sonora aequalis - Jalisco-Zacatecas Groundsnake
- Sonora michoacanensis - Michoacán Groundsnake
- Sonora mutabilis - Mexican Groundsnake
- Sonora semiannulata - Western Groundsnake
- S. s. semiannulata - Variable Groundsnake
- S. s. taylori - Southern Texas Groundsnake
- Spilotes - Tiger Tree Snakes
- Spilotes pullatus - Tropical Tree Snake
- S. p. mexicanus - Tiger Tree Snake
- Spilotes pullatus - Tropical Tree Snake
- Stenorrhina - Scorpion-eating Snakes
- Stenorrhina degenhardtii - Degenhardt's Scorpion-eating Snake
- S. d. mexicana - Mexican Scorpion-eating Snake
- Stenorrhina freminvillei - Freminville's Scorpion-eating Snake
- Stenorrhina degenhardtii - Degenhardt's Scorpion-eating Snake
- Storeria - North American Brownsnakes
- Storeria dekayi - Dekay's Brownsnake
- S. d. anomala - Dugès's Brownsnake
- S. d. dekayi - Northern Brownsnake
- S. d. limnetes - Marsh Brownsnake
- S. d. temporalineata - Trapido's Brownsnake
- S. d. texana - Texas Brownsnake
- S. d. tropica - Tropical Brownsnake
- S. d. wrightorum - Midland Brownsnake
- Storeria hidalgoensis - Mexican Yellow-bellied Brownsnake
- Storeria occipitomaculata - Red-bellied Snake
- S. o. obscura - Florida Red-bellied Snake
- S. o. occipitomaculata - Northern Red-bellied Snake
- S. o. pahasapae - Black Hills Red-bellied Snake
- Storeria storerioides - Mexican Brownsnake
- Storeria victa - Florida Brownsnake
- Storeria dekayi - Dekay's Brownsnake
- Symphimus - White-lipped Snakes
- Symphimus leucostomus - Tehuantepec White-lipped Snake
- Symphimus mayae - Yucatán White-lipped Snake
- Sympholis - Mexican Short-tailed Snakes
- Sympholis lippiens - Mexican Short-tailed Snake
- Tantalophis - Oaxacan Cat-eyed Snakes
- Tantalophis discolor - Oaxacan Cat-eyed Snake
- Tantilla - Black-headed, Flat-headed, Crowned & Centipede Snakes
- Tantilla atriceps - Mexican Black-headed Snake
- Tantilla bocourti - Bocourt's Black-headed Snake
- Tantilla briggsi - Brigg's Centipede Snake
- Tantilla calamarina - Pacific Coast Centipede Snake
- Tantilla cascadae - Michoacán Centipede Snake
- Tantilla coronadoi - Guerreran Centipede Snake
- Tantilla coronata - Southeastern Crowned Snake
- Tantilla cucullata - Trans-pecos Black-headed Snake
- Tantilla cuniculator - Peten Centipede Snake
- Tantilla deppei - Deppe's Centipede Snake
- Tantilla flavilineata - Yellow-lined Centipede Snake
- Tantilla gracilis - Flat-headed Snake
- Tantilla hobartsmithi - Smith's Black-headed Snake
- Tantilla impensa - Central Guatemalan Centipede Snake
- Tantilla johnsoni - Chiapan Centipede Snake
- Tantilla moesta - Black-bellied Centipede Snake
- Tantilla nigriceps - Plains Black-headed Snake
- Tantilla oaxacae - Oaxacan Centipede Snake
- Tantilla oolitica - Rim Rock Crowned Snake
- Tantilla planiceps - Western Black-headed Snake
- Tantilla relicta - Florida Crowned Snake
- T. r. neilli - Central Florida Crowned Snake
- T. r. pamlica - Coastal Dunes Crowned Snake
- T. r. relicta - Peninsula Crowned Snake
- Tantilla robusta - Robust Centipede Snake
- Tantilla rubra - Red Black-headed Snake
- Tantilla schistosa - Red Earth Centipede Snake
- Tantilla sertula - Balsas Centipede Snake
- Tantilla shawi - Sierra Madre Centipede Snake
- Tantilla slavensi - Slaven's Centipede Snake
- Tantilla striata - Twin-spotted Centipede Snake
- Tantilla tayrae - Tayra's Centipede Snake
- Tantilla triseriata - Three-lined Centipede Snake
- Tantilla vulcani - Volcanic Highland Centipede Snake
- Tantilla wilcoxi - Chihuahuan Black-headed Snake
- Tantilla yaquia - Yaqui Black-headed Snake
- Tantillita - Dwarf Short-tailed Snakes
- Tantillita brevissima - Speckled Dwarf Short-tailed Snakes
- Tantillita canula - Yucatan Dwarf Short-tailed Snake
- Tantillita lintoni - Linton's Dwarf Short-tailed Snake
- T. l. rozellae - Rozella's Dwarf Short-tailed Snake
- Thamnophis - North American Garter & Ribbon Snakes
- Thamnophis atratus - Aquatic Gartersnake
- T. a. atratus - Santa Cruz Gartersnake
- T. a. hydrophilus - Oregon Gartersnake
- T. a. zaxanthus - Diablo Gartersnake
- Thamnophis bogerti - Bogert's Gartersnake
- Thamnophis brachystoma - Short-headed Gartersnake
- Thamnophis butleri - Butler's Gartersnake
- Thamnophis chrysocephalus - Goldenhead Gartersnake
- Thamnophis conanti - Conant's Gartersnake
- Thamnophis couchii - Sierra Gartersnake
- Thamnophis cyrtopsis - Black-necked Gartersnake
- T. c. collaris - Tropical Black-necked Gartersnake
- T. c. cyrtopsis - Western Black-necked Gartersnake
- T. c. ocellatus - Eastern Black-necked Gartersnake
- Thamnophis elegans - Terrestrial Gartersnake
- T. e. elegans - Mountain Gartersnake
- T. e. hueyi - Isla San Pedro Martir Gartersnake
- T. e. terrestris - Coast Gartersnake
- T. e. vagrans - Wandering Gartersnake
- Thamnophis eques - Mexican Gartersnake
- T. e. carmenensis - Tlaxcala Gartersnake
- T. e. cuitzeonensis - Lake Cuitzeo Mexican Gartersnake
- T. e. diluvialis - Jalisco Mexican Gartersnake
- T. e. eques - Southern Mexican Gartersnake
- T. e. insperatus - Lake Zacapu Mexican Gartersnake
- T. e. megalops - Brown Gartersnake
- T. e. obscurus - Obscure Mexican Gartersnake
- T. e. patzcuaroensis - Lake Patzucuaro Mexican Gartersnake
- T. e. scotti - Scott's Gartersnake
- T. e. virgatenuis - Western Montane Mexican Gartersnake
- Thamnophis errans - Mexican Wandering Gartersnake
- Thamnophis exsul - Exiled Mexican Gartersnake
- Thamnophis fulvus - Mesoamerican Highlands Gartersnake
- Thamnophis gigas - Giant Gartersnake
- Thamnophis godmani - Godman's Gartersnake
- Thamnophis hammondii - Two-striped Gartersnake
- Thamnophis lineri - Liner's Gartersnake
- Thamnophis marcianus - Checkered Gartersnake
- T. m. marcianus - Checkered Gartersnake
- T. m. praeocularis - Yucatecan Checkered Gartersnake
- Thamnophis melanogaster - Mexican Black-bellied Gartersnake
- T. m. canescens - Gray Black-bellied Gartersnake
- T. m. chihuahuanensis - Chihuahuan Black-bellied Gartersnake
- T. m. linearis - Lined Black-bellied Gartersnake
- T. m. melanogaster - Mexican Black-bellied Gartersnake
- Thamnophis mendax - Tamaulipas Montane Gartersnake
- Thamnophis nigronuchalis - Durangan Spotted Gartersnake
- Thamnophis ordinoides - Northwestern Gartersnake
- Thamnophis postremus - Tepalcatepec Valley Gartersnake
- Thamnophis proximus - Western Ribbonsnake
- T. p. alpinus - Chiapas Highland Ribbonsnake
- T. p. diabolicus - Arid Land Ribbonsnake
- T. p. orarius - Gulf Coast Ribbonsnake
- T. p. proximus - Orange-striped Ribbonsnake
- T. p. rubrilineatus - Red-striped Ribbonsnake
- T. p. rutiloris - Gulf Coast Ribbonsnake
- Thamnophis pulchrilatus - Mexican Highland Gartersnake
- Thamnophis radix - Plains Gartersnake
- Thamnophis rossmani - Rossman's Gartersnake
- Thamnophis rufipunctatus - Narrow-headed Gartersnake
- Thamnophis sauritus - Eastern Ribbonsnake
- T. s. nitae - Blue-striped Ribbonsnake
- T. s. sackenii - Peninsula Ribbonsnake
- T. s. sauritus - Eastern Ribbonsnake
- T. s. septentrionalis - Northern Ribbonsnake
- Thamnophis scalaris - Long-tailed Alpine Gartersnake
- Thamnophis scaliger - Short-tailed Alpine Gartersnake
- Thamnophis sirtalis - Common Gartersnake
- T. s. annectens - Texas Gartersnake
- T. s. concinnus - Red-Spotted Gartersnake
- T. s. dorsalis - New Mexico Gartersnake
- T. s. fitchi - Valley Gartersnake
- T. s. infernalis - California Red-sided Gartersnake
- T. s. pallidulus - Maritime Gartersnake
- T. s. parietalis - Red-sided Gartersnake
- T. s. pickeringii - Puget Sound Gartersnake
- T. s. semifasciatus - Chicago Gartersnake
- T. s. similis - Blue-striped Gartersnake
- T. s. sirtalis - Eastern Gartersnake
- T. s. tetrataenia - San Francisco Gartersnake
- Thamnophis sumichrasti - Sumichrast's Gartersnake
- Thamnophis validus - Mexican West Coast Gartersnake
- T. v. celaeno - Cape Gartersnake
- T. v. isabelleae - Colima Gartersnake
- T. v. thamnophisoides - Tepic Gartersnake
- T. v. validus - Pacific Gartersnake
- Thamnophis atratus - Aquatic Gartersnake
- Tretanorhinus - Middle American Swamp Snakes
- Tretanorhinus nigroluteus - Orange-bellied Swamp Snake
- Trimorphodon - Lyresnakes
- Trimorphodon biscutatus - Western Lyresnake
- T. b. biscutatus - Western Lyresnake
- T. b. lambda - Sonoran Lyresnake
- T. b. lyrophanes - Baja California Lyresnake
- T. b. quadruplex - Central American Lyresnake
- Trimorphodon tau - Mexican Lyresnake
- T. t. latifasciatus - Black-headed Lyresnake
- T. t. tau - Mexican Lyresnake
- Trimorphodon vilkinsonii - Texas Lyresnake
- Trimorphodon biscutatus - Western Lyresnake
- Tropidoclonion - Lined Snakes
- Tropidoclonion lineatum - Lined Snake
- Tropidodipsas - False Middle American Snail Eaters
- Tropidodipsas annulifera - Western Snail-eating Sucker
- Tropidodipsas fasciata - Banded Snail Sucker
- T. f. fasciatus - Banded Snail Sucker
- T. f. guerreroensis - Guerreran Snail Sucker
- T. f. subannulata - Muller's Snail Sucker
- Tropidodipsas fischeri - Fischer's Snail-eating Snake
- T. f. fischeri - Fischer's Snail-eating Snake
- Tropidodipsas philippii - Philippi's Snail-eating Sucker
- Tropidodipsas sartorii - Terrestrial Snail Sucker
- T. s. annulatus - Annulated Snail Sucker
- T. s. macdougalli - MacDougall's Snail Sucker
- T. s. sartorii - Sartori's Snail Sucker
- Tropidodipsas zweifeli - Zweifel's Snail-eating Sucker
- Typhlops - Common Blind Wormsnakes
- Typhlops microstomus - Yucatecan Blindsnake
- Typhlops tenuis - Coffee Blindsnake
- Ungaliophis - Central American Dwarf Boas
- Ungaliophis continentalis - Isthmian Dwarf Boa
- Virginia - North American Earthsnakes
- Virginia striatula - Rough Earthsnake
- Virginia valeriae - Smooth Earthsnake
- V. v. elegans - Western Smooth Earthsnake
- V. v. pulchra - Mountain Earthsnake
- V. v. valeriae - Eastern Smooth Earthsnake
- Xenodon - False Fer-de-Lance
- Xenodon rabdocephalus - False Fer-de-Lance
- X. r. mexicanus - Mexican False Fer-de-Lance
- Xenodon rabdocephalus - False Fer-de-Lance