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Suborder Serpentes

ser' pen tEz, snakes


General Information
A snake is a backboned animal with a long, legless body covered by dry scales. The eyes of a snake are covered by clear scales instead of movable eyelids, meaning that its eyes are always open. All snakes have a narrow, forked tongue, which is used to bring odors to a special sense organ in the mouth, allowing them to follow the scent trails of their prey.
Copperhead (Agkistrodon contortrix)Copperhead (Angkistrodon contortrix)
This pit viper is most easily identified by its copper-colored head (hence the name). Although a copperhead bite can be serious for a human, it is rarely fatal.
Snake BodiesSnake Bodies
Snakes vary greatly in body shape. Some have stout bodies, while others have long, thin bodies. The bodies of sea snakes are flattened from side to side.
Cottonmouth (Angkistrodon piscivorus)Cottonmouth (Angkistrodon piscivorus)
This pit viper gets its common name from the bright white lining inside its mouth. Because it is almost always found in or very near water, it is also known as a water moccasin.
The Skeleton of a SnakeThe Skeleton of a Snake
The main parts of a snake's skeleton are (1) the skull, (2) vertebrae, and (3) ribs. A few snakes, such as blind snakes, boas, and pythons, have vestiges of hind legs or hipbones.
Gaboon Viper (Bitis gabonicus)Gaboon Viper (Bitis gabonica)
The largest viper in Africa, the Gaboon can grow to over 7 feet in length, with an average length of just under 4 feet, and weighs 15 to 22 pounds. It also has the largest fangs of all venomous snakes, about 2 inches long in a full-grown adult.
The Skin of a SnakeThe Skin of a Snake
Snake skin has three layers. Only the outer, thinnest layer is peeled away when the snake sheds.
Boa Constrictor (Boa constrictor)Boa Constrictor (Boa constrictor)
The most distinctive feature of this snake is the head, which has a dark stripe running dorsally from the snout to the back of the head, a dark triangle between the snout and eyes, and a continuation of that triangle behind each eye that slants downward towards the jaw.
Snake SensesSnake Senses
Snakes do not have especially keen senses of sight or hearing. They rely instead on special sense organs to provide them with information about their environment.
Smooth Snake (Coronella austriaca)Smooth Snake (Coronella austriaca)
This snake is distinguished from similar species by its uniformly colored belly. The common name 'smooth snake' refers to the scales, which lack the keel of other snakes.
Snake LocomotionSnake Locomotion
Snakes have four main methods of moving about: (1) lateral undulation, (2) rectilinear movement, (3) concertina movement, and (4) sidewinding. Some snakes also move in other, unusual ways.
Black Mamba (Dendroaspis polylepis)The Black Mamba (Dendroaspis polylepis)
is named for the lining of its mouth, which is purple-black and is displayed when threatened. Capable of speeds up to 14 mph, it is one of the fastest snakes in the world. It is also one of the dealiest snakes in the world, with a venom that is 100% lethal to humans without an antivenin.
Snake Fangs and VenomSnake Fangs and Venom
Poisonous snakes use venom because it is a very good way to capture prey. There is no need for a poisonous snake to spend hours and a great deal of energy squeezing its prey, and there is no need to chase after prey. The snake simply injects its venom and waits for it to take effect.
Yellow Anaconda (Eunectes notaeus)Yellow Anaconda (Eunectes notaeus)
Much smaller than its cousin the green anaconda, the yellow anaconda is 9-15 feet long and weighs 66-88 pounds, with females being larger than males. It has yellowish-green scales with brown or blackish bands and overlapping spots that wrap around the entire body.
Grass Snake (Natrix natrix)Grass Snake (Natrix natrix)
The characteristic feature of this snake is a yellowish, orange, pink or white patch either side of the neck forming an incomplete collar or ring.
King Cobra (Ophiophagus hannah)King Cobra (Ophiophagus hannah)
A king cobra will not attack unless cornered or provoked -- with the exception of nesting females, which may attack without provocation. The venom of the king cobra is very potent -- one gram can kill 150 people. The venom of a juvenile king cobra is just as potent as that of an adult.
Reticulated Python (Python reticulatus)Reticulated Python (Python reticulatus)
This snake is easily distinguished by its huge size and the series of irregular diamond shapes positioned dorsally along the back. The longest snake in the world, the reticulated python reguarly reaches lengths of 25 feet or more. It is second to the green anaconda when it comes to overall mass, however.
Madagascar Tree Boat (Sanzinia madagascariensis)Madagascar Tree Boa (Sanzinia madagascariensis)
This snake is unique to Madagascar, where it lives in forested areas near bodies of water. It is endangered due to increased farming and housing development, and is now found only in protected areas.

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