Rolf Nussbaumer / Western Cottonmouth snake (Agkistrodon piscivorus leucostoma) on lake flicking tongue. Fennessey Ranch, Refugio, Coastal Bend, Texas Coast, USA

Rolf Nussbaumer / Western Cottonmouth (Agkistrodon piscivorus leucostoma) head portrait in grass, Fennessey Ranch, Refugio, Coastal Bend, Texas Coast, USA

Edwin Giesbers / Copperhead snake {Agkistrodon contortrix} captive, from USA

Rolf Nussbaumer / Juvenile Western cottonmouth snake {Agkistrodon piscivorus leucostoma} on American Lotus {Nelumbo lutea} lily pad, Welder Wildlife Refuge, Sinton, Texas, USA.

Michael D. Kern / Southern copperhead snake (Agkistrodon contortrix contortrix) captive, from southern USA

Michael D. Kern / Southern copperhead snake (Agkistrodon contortrix contortrix) captive, from southern USA

Daniel Heuclin / Mexican Moccasin / Cantil Snake (Agkistrodon bilineatus taylori) against white background. Endemic to Mexico.

Daniel Heuclin / Copperhead snake (Agkistrodon contortrix) found in South Eastern USA, captive

Pete Oxford / Copperhead (Agkistrodon contortrix) Northern Georgia, USA, captive

Pete Oxford / Copperhead (Agkistrodon contortrix) Northern Georgia, USA, captive

John Cancalosi / Cantil Pitviper (Agkistrodon bilineatus) coiled. Costa Rican tropical rainforest.

John Abbott / Southern Copperhead snake (Agkistrodon contortrix) camouflaged on leaves on forest floor, Angelina National Forest, Texas, USA, March

Pete Oxford / Copperhead (Agkistrodon contortrix) snake, native to south eastern United States

Daniel Heuclin / Western Cottonmouth / Water Mocassin (Agkistrodon piscivorus leucostoma) swimming in shallow water. Controlled conditions. Lake Fausse-Pointe, Louisiana, November.

Daniel Heuclin / Western Cottonmouth / Water Mocassin (Agkistrodon piscivorus leucostoma) resting on a rock by water. Controlled conditions. Lake Fausse-Pointe, Louisiana, November.

Konstantin Mikhailov / Brown Mamushi snake (Agkistrodon saxatilis), Mongolia, Gobi Desert

Rolf Nussbaumer / Western Cottonmouth snake (Agkistrodon piscivorus leucostoma) in defensive posture. Fennessey Ranch, Refugio, Coastal Bend, Texas Coast, USA

Rolf Nussbaumer / Western Cottonmouth snake (Agkistrodon piscivorus leucostoma) on lake flicking tongue. Fennessey Ranch, Refugio, Coastal Bend, Texas Coast, USA

Rolf Nussbaumer / Western Cottonmouth snake (Agkistrodon piscivorus leucostoma) on lake flicking tongue. Fennessey Ranch, Refugio, Coastal Bend, Texas Coast, USA

Tony Phelps / Copperhead snake {Agkistrodon contortrix} Captive, from north America

Tony Phelps / Copperhead snake {Agkistrodon contortrix} captive, from Virginia, USA

Jabruson / Dried snake (Agkistrodon acutus) sold for medicine. Kowloon, Hong Kong, China

Philippe Clement / Broad-banded copperhead (Agkistrodon contortrix laticinctus) captive, Costa Rica

Philippe Clement / Broad-banded copperhead (Agkistrodon contortrix laticinctus) captive, Costa Rica

Michael & Patricia Fogden / Cantil (Agkistrodon bilineatus) venomous species amid leaf litter, Costa Rica

Konstantin Mikhailov / Brown mamushi snake (Agkistrodon saxatilis) the only venomous snake in Gobi Desert, Mongolia

Mary McDonald / Southern copperhead {Agkistrodon contortrix} captive, from SE USA

Yuri Shibnev / Brown mamushi {Agkistrodon saxatilis} Ussuriland, Far East Russia

Mary McDonald / Mexican cantil {Agkistrodon bilineatus} captive, from Mexico

LYNN M. STONE / Osage copperhead {Agkistrodon contortrix phaeogaster} captive, from USA

Mary McDonald / Broad banded copperhead snake (Agkistrodon contortrix) USA, captive

LYNN M. STONE / Western cottonmouth {Agkistrodon piscivorus leucostoma} captive

Barry Mansell / Florida cottonmouth {Agkistrodon piscivorus conanti} Florida, USA

Rolf Nussbaumer / Juvenile Western cottonmouth {Agkistrodon piscivorus leucostoma} resting on American Lotus {Nelumbo lutea} lily pad, Welder Wildlife Refuge, Sinton, Texas, USA.

Rolf Nussbaumer / Juvenile Western cottonmouth snake {Agkistrodon piscivorus leucostoma} Welder Wildlife Refuge, Sinton, Texas, USA.

Todd Pusser / Albino Eastern cottonmouth / Water moccasin snake {Thamnophis sauritus}, USA.

Todd Pusser / Copperhead snake {Agkistrodon contortrix} camouflaged among leaves, USA.

Todd Pusser / Copperhead snake {Agkistrodon contortrix}, North Carolina, USA.

LYNN M. STONE / Western cottonmouth swimming {Agkistrodon piscivorus leucostoma} captive

Yva Momatiuk & John Eastcott / Cottonmouth (Agkistrodon piscivorus) juvenile draped over tree branch, southern Louisiana

Norbert Wu / Cottonmouth (Agkistrodon piscivorus) venomous, Florida

Robert Valentic / American copperhead {Agkistrodon contortrix laticinctus} captive

LYNN M. STONE / Western cottonmouth / water moccasin snake {Agkistrodon piscivorus leucostoma} Texas, USA

Barry Mansell / Florida cottonmouth snake shows white mouth in threat display {Agkistrodon piscivorus conanti}

Rod Williams / Young Cantil / Tropical moccasin snake using tail as lure or as warning {Agkistrodon bilineatus} occurrs Central America

Barry Mansell / Florida Cottonmouth (Agkistrodon piscivorus conanti) dark cheek stripes indicate this is a juvenile, North Florida, USA

Barry Mansell / Florida Cottonmouth (Agkistrodon piscivorus conanti) defensive strike shows dark cheek stripes indicating this is a juvenile, North Florida, USA

Tony Phelps / Cantil / Tropical Moccassin (Agkistrodon bilineatus) sensing air with forked tongue, Captive, native to North Mexico.

Tony Phelps / Cantil / Tropical Moccassin (Agkistrodon bilineatus) Captive, native to North Mexico.

LYNN M. STONE / Water moccasin snake / Cottonmouth. USA {Agkristrodon piscivorus}