Boomslang Snake

The average adult boomslang is 100-160 cm (3¼-5¼ feet) in total length, but some exceed 183 cm (6 feet). The eyes are exceptionally large, and the head has a characteristic egg-like shape. Coloration is very variable. Males are light green with black or blue scale edges, but adult females may be brown.
The head is distinct from the neck. The canthus rostralis is distinct. The pupil of the very large eye is round. The maxillary teeth are small anteriorly, 7 or 8, followed by three very large grooved fangs situated below the eye. The mandibular teeth are subequal. The body is slightly compressed. The dorsal scales are very narrow, oblique, strongly keeled, with apical pits, arranged in 19 or 21 rows. The tail is long, and the subcaudals are paired. Ventrals are 164-201; the anal plate is divided; and the subcaudals are 91-131.

Behavior and diet
Boomslangs are diurnal and largely arboreal. Their diet includes chameleons and other arboreal lizards, frogs, and occasionally small mammals, birds, and eggs from nesting birds, all of which they swallow whole. During cool weather, they will hibernate for moderate periods, often curling up inside the enclosed nests of birds such as weavers.
Venom
Many venomous members of the family Colubridae are harmless to humans because of small venom glands, weak venom, or inefficient fangs. However, the boomslang is a notable exception in that it has a highly potent venom, which it delivers through large fangs that are located in the back of the jaw. Boomslangs open their jaws 90 degrees when biting. The venom of the boomslang is primarily a hemotoxin; it disables the blood clotting process and the victim may well die as a result of internal and external bleeding. Other signs and symptoms include headache, nausea, sleepiness and mental disorders.
Because the venom is slow to act, symptoms may not be manifest until many hours after the bite. On one hand, this provides time for procuring the antivenom, while on the other it may lead victims to underestimate the seriousness of the bite. Snakes of any species may sometimes fail to inject venom when they bite, so after a few hours without any noticeable effects, victims of boomslang bites may believe (wrongly) their injury is not serious.
An adult boomslang has 1.6–8 mg of venom.[8] Various sources give figures ranging from 0.06 - 0.72 mg/kg being sufficient to kill mice in 50% of cases, if the venom reaches a vein (LD50).
In 1957, well-known herpetologist Karl Schmidt died after being bitten by a boomslang. D.S. Chapman states that between 1919 and 1962 there were eight serious human envenomations by boomslangs, two of which were fatal. The South African Vaccine Producers (formerly South African Institute of Medical Research) manufactures a monovalent antivenin for use in boomslang envenomations.
The boomslang is a timid snake, and bites generally occur only when people attempt to handle, catch or kill the animal. The above data suggest boomslangs are unlikely to be a significant source of human fatalities throughout their distribution range.

Red Spitting Cobra

This is a relatively medium sized cobra, attaining lengths between 0.7 to 1.2 meters (2.3 to 3.9 ft), but they may grow maximum lengths of around 1.5 meters (4.9 ft) in very rare cases This is often thought of as an attractive species, it is usually bright salmon red contrasting with a broad black throat band and subocular teardrop markings. However, the colour of this species does have variation and this variation usually depends on where in Africa a particular specimen is found. For example, specimens from southern Kenya and northern Tanzania have an orange-red colour, with a broad dark blue or black throat band. In some specimens we also see two or three throat bands but this is uncommon for specimens from East Africa. The ventral side is also reddish in colour, sometimes the throat area may be a creamy white. Specimens from other areas can be yellow, pinkish, pink-grey, pale red or steel grey. Most specimens will have a throat band, but this throat band will fade or even sometimes disappear in larger adults. The true red specimens will become reddish-brown in colour as they age and grow in size. The body of this snake is slightly depressed, tapered and moderately slender with a medium length tail. It is slightly compressed dorsoventrally and subcylindrical posteriorly. The head is broad, flattened and slightly distinct from the neck. The canthus is distinct and the snout is rounded. The eyes are medium to large in size with round pupils. Dorsal scales are smooth and strongly oblique.

Behavior
Red spitting cobras are terrestrial, fast and alert snakes. Adults specimens of this species are nocturnal, while juveniles are more active both during the day. Adults like to hide in termite mounds, old logs, in holes, brush piles or any other ground cover during the day.They are often found near water holes where they hunt on pythons which is their preferred prey. They are also known to be cannibalistic, this could be the reason that the juveniles and smaller specimens are diurnal while adults are nocturnal.When threatened, it rears up and displays a typical cobra hood. It may also hiss loudly. If the intruder does not retreat, it may sprays jets of semin to the face of the intruder. Semin that gets into the eyes can cause burning pain and blindness. Even so, this snake seldom causes fatalities in humans.
Venom
This species, like most spitting cobra, contains a mixture of neurotoxic and cytotoxic. Bite symptoms include slight pain around the wound and numbness of lips and tongue. Although it rarely causes human fatalities, survivors are usually disfigured. The murine IP LD50 value for this snake is 2 mg/kg.
In September 2011, a snake keeper from the Eastern Cape in South Africa died shortly after a Red spitting cobra sprayed venom into his face whilst he and a friend were photographing the snake. It is believed that some of the venom entered his nasal passages and led to anaphylactic shock. The fact that he was asthmatic is believed to have contributed to his fatal reaction.

Snouted cobra

The snouted cobra is a relatively large species of cobra. Adult specimens average between 1.2 to 1.8 metres (3.9 to 5.9 ft) in length but they may reach lengths of 2.5 metres (8.2 ft). Colouration of dorsal scales may vary from yellowish to greyish brown, dark brown or blue-black. Ventral scale colouration is yellow with darker mottles. A banded phase occurs throughout the species' range and is blue-black with 7-11 yellow to yellow-brown cross bars, the lighter bands being half the width of the darker bands. The latter colour phase is more common in males. Ventrally, yellow mottled with black. A darker throat band is present and is usually more prominent in juveniles
Habitat and ecology
Snouted cobras inhabit arid and moist savanna, particularly in bushveld and lowveld areas. It is not found in forests. As a large cobra, it likes to have a permanent home base or lair in an abandoned termite mound where it will reside for years if left undisturbed. It is a nocturnal species, foraging for food from dusk onwards, often venturing into poultry runs. It enjoys basking in the sun during the day near its lair or retreat. Not a particularly aggressive species, but will assume a formidable posture if cornered. Very large adults are able to lift as much as half a metre of the body off the ground while spreading a wide, impressive hood. However, given the opportunity it will escape to the nearest hole or crevice. Like the Rinkhals it may sham death if threatened, but this is rare. It preys on toads, rodents, birds and their eggs, lizards and other snakes, especially puff adders (Bitis arietans). It often raids poultry runs and can become a nuisance. It is preyed upon by birds of prey and other snakes.
Venom
It is a highly venomous species with neurotoxic venom. A bite can affect breathing and if left untreated may cause respiratory failure and death. Initial symptoms include pain and local swelling that may result in blistering. Typically, victims are bitten on the lower leg, usually at night.
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Cottonmouth snake

The name cotton mouth is originate from the cotton like color in its mouth.It is a widespread misunderstanding that the Cottonmouth snake is aggressive compared to other snakes.
In a study by Gibbons and Dorcas (1998)1, this misunderstanding was challenged when data suggested that the Cottonmouth is not as aggressive as people believe.
Cottonmouth snake like to eat reptiles, fish, amphibians, invertebrates, birds, and mammals.
The Cottonmouth produces its venom in glands close to where the jaws join. When it bites, the muscles around the glands squeeze venom from the glands through ducts through to the fangs. The venom destroys blood cells and reduces the normal coagulation and clotting abilities of the blood. This results in hemorrhaging where the poison has penetrated into the prey.

Black Mamba

The Black Mamba snake also known as Dendroaspis polylepis is one of Africa’s most dangerous and feared snakes. The black mamba is the largest venomous snake in Africa and the second largest snake in the world, after the King Cobra. Adult black mambas have an average length of 2.5 meters or 8.2 feet and a maximum length of 4.5 meters or around 14 feet. The Back Mamba is also one of the fastest land snakes in the world. It has the capability to reach speeds in excess of 12 mph or 20km/hr. It mainly uses this speed the escape danger rather than capturing prey.
The Black Mamba gets its name not because the color of its body, but because it has a black inky color mouth. The black mamba has either a dark olive, olive green, grey brown or metal color skin depending on what area on the country the Black Mamba is found. As Black Mamba’s begin to age, their skin starts to become darker.
Black Mambas are elapid snakes, which mean they are venomous snakes found in tropical or subtropical regions around the word including the Indian and Pacific Ocean. Elapid snakes are characterized by having a set of hollow, fixed fangs through which they inject venom. Black Mambas venom contains powerful, fast-acting neurotoxins and cardiotoxins, including calciseptine. Calcoseptine contains 60 amino acids with four disulfide bonds and is one of the main culprits for the Black Mambas prey to stop pumping blood through its veins.

Each bite that the Black Mamba delivers has about 100-120 mg of venom on average and it can deliver up to 400 mg. If the venom reaches a vein, .25 mg/kg is enough to kill a full-size human in half of the cases. The initial symptom of the bite is local pain in the bite area, then the viction experiences a tingling sensation in the mouth and extremities, double vision, tunnel vision, severe confusion, fever, excessive perspiration, foaming of the mouth and nose, and a lack of muscle control.
If the victim does not receive medical attention, symptoms rapidly progress to severe abdominal pain, nausea and vomiting, shortness of breath), and paralysis. Eventually, the victim experiences convulsions, respiratory arrest, coma, and then death. Without antivenom, the mortality rate is nearly 100%, the highest among venomous snakes.