Naja atra
Encyclopedia
The Chinese cobra

The Chinese cobra (Naja atra, also known as Taiwanese cobra, is a species of genus Naja
Naja
Naja is a genus of venomous elapid snakes. Although there are several other genera that share the common name, Naja are the most recognized and most widespread group of snakes commonly known as cobras. The genus Naja consists of 20 to 22 species, but has undergone several taxonomic revisions in...

 found mostly in southern China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...

 and Taiwan
Taiwan
Taiwan , also known, especially in the past, as Formosa , is the largest island of the same-named island group of East Asia in the western Pacific Ocean and located off the southeastern coast of mainland China. The island forms over 99% of the current territory of the Republic of China following...

. Theodore Edward Cantor first described the iridescent black monocled cobra from Chusan Island in 1842. It is one of the most prevalent venomous snakes in Taiwan
Taiwan
Taiwan , also known, especially in the past, as Formosa , is the largest island of the same-named island group of East Asia in the western Pacific Ocean and located off the southeastern coast of mainland China. The island forms over 99% of the current territory of the Republic of China following...

, which has caused many snakebite
Snakebite
A snakebite is an injury caused by a bite from a snake, often resulting in puncture wounds inflicted by the animal's fangs and sometimes resulting in envenomation. Although the majority of snake species are non-venomous and typically kill their prey with constriction rather than venom, venomous...

 incidents to humans.

Characteristics

This medium-sized snake, usually 1.2–1.5 m (3.9–4.9 ft) long, reaches a maximum length of 1.94 metres (6.4 ft) (male) and 1.64 metres (5.4 ft) (female). Large specimens of 2.3 metres (7.5 ft) in length have been reported. The dorsal color of the Chinese Cobra is usually brown, grey or black, with or without narrow, light transverse lines at irregular intervals which are especially prominent in juveniles.
The hood mark shape of the snake is highly variable: spectacle, mask, horseshoe or O-shape; sometimes linking to light throat area. It has clearly defined throat area usually with a black transverse band and 2 black spots above the band.

Scalation

23-29 scale rows around hood (usually 25-27); 19-21 just ahead mid-body (usually 21); ventral scales 161-180 (usually 171 in males, 173 in females); subcaudal scales 37-51 pairs (usually 48 in males, 46 in females).

Identification

The Chinese cobra is easily confused with the Monocled Cobra (Naja kaouthia). But it is most easily distinguished by virtue of having lower ventral and subcaudal scale counts, particular when sex is taken into account.

Distribution

This species is found in Taiwan
Taiwan
Taiwan , also known, especially in the past, as Formosa , is the largest island of the same-named island group of East Asia in the western Pacific Ocean and located off the southeastern coast of mainland China. The island forms over 99% of the current territory of the Republic of China following...

, southeastern China (including Hainan
Hainan
Hainan is the smallest province of the People's Republic of China . Although the province comprises some two hundred islands scattered among three archipelagos off the southern coast, of its land mass is Hainan Island , from which the province takes its name...

), Hong Kong
Hong Kong
Hong Kong is one of two Special Administrative Regions of the People's Republic of China , the other being Macau. A city-state situated on China's south coast and enclosed by the Pearl River Delta and South China Sea, it is renowned for its expansive skyline and deep natural harbour...

, northern Laos
Laos
Laos Lao: ສາທາລະນະລັດ ປະຊາທິປະໄຕ ປະຊາຊົນລາວ Sathalanalat Paxathipatai Paxaxon Lao, officially the Lao People's Democratic Republic, is a landlocked country in Southeast Asia, bordered by Burma and China to the northwest, Vietnam to the east, Cambodia to the south and Thailand to the west...

, and northern Vietnam
Vietnam
Vietnam – sometimes spelled Viet Nam , officially the Socialist Republic of Vietnam – is the easternmost country on the Indochina Peninsula in Southeast Asia. It is bordered by China to the north, Laos to the northwest, Cambodia to the southwest, and the South China Sea –...

. Its typical habitat is woodland
Woodland
Ecologically, a woodland is a low-density forest forming open habitats with plenty of sunlight and limited shade. Woodlands may support an understory of shrubs and herbaceous plants including grasses. Woodland may form a transition to shrubland under drier conditions or during early stages of...

s, shrublands, grasslands, and mangroves. It usually hides under leaves, sticks, and rocks.

Behavior

The Chinese cobra has a characteristic defensive behavior. When threatened, this snake raises one third of the forebody, hissing loudly, and the characteristic hood on the neck is expanded. The snake may also occasionally spit venom. The Chinese cobra usually escapes to avoid confrontation with humans, but strikes readily if provoked.
The Chinese Cobra mainly preys on rodent
Rodent
Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....

s, frogs, toads and other snakes. It is active during both the day and night.

Venom

The Chinese cobra's venom consists mainly of cobratoxin
Cobratoxin
α-Cobratoxin is a substance of the venom of certain Naja cobras. It is a muscle-type nicotinic acetylcholine receptor antagonist, which causes paralysis by preventing the binding of acetylcholine to the nAChR.-Source:...

s (a type of neurotoxin
Neurotoxin
A neurotoxin is a toxin that acts specifically on nerve cells , usually by interacting with membrane proteins such as ion channels. Some sources are more general, and define the effect of neurotoxins as occurring at nerve tissue...

s), hemotoxin
Hemotoxin
Hemotoxins, haemotoxins or hematotoxins are toxins that destroy red blood cells , disrupt blood clotting, and/or cause organ degeneration and generalized tissue damage. The term hemotoxin is to some degree a misnomer since toxins that damage the blood also damage other tissues...

s and cardiotoxins. The values of its venom in mice
MICE
-Fiction:*Mice , alien species in The Hitchhiker's Guide to the Galaxy*The Mice -Acronyms:* "Meetings, Incentives, Conferencing, Exhibitions", facilities terminology for events...

 are 0.29 mg/kg SC, 0.345 mg/kg IV
Intravenous therapy
Intravenous therapy or IV therapy is the infusion of liquid substances directly into a vein. The word intravenous simply means "within a vein". Therapies administered intravenously are often called specialty pharmaceuticals...

 and 0.53 mg/kg IC. The average venom yield from this snake is about 250.8 mg
Mg
MG, M.G., M-G and variants may refer to:Business* MG Cars , a British automobile manufacturer, now part of SAIC* Champion Air , an American charter airline with IATA code MGEducation...

. Some individuals (mostly the specimens from Guizhou
Guizhou
' is a province of the People's Republic of China located in the southwestern part of the country. Its provincial capital city is Guiyang.- History :...

 Province) might spit venom towards the enemy with a distance of 2 metres (6.6 ft).

Local symptoms in victims caused by Chinese cobra are wound darkening, localized redness and swelling
Swelling
Swelling , is the enlargement of tissue.Swelling can also mean:*Die swell, the increase of volume of material due to absorption of a solvent, common for plastic polymers*Neutron-induced swelling caused by neutron radiation....

, pain
Pain
Pain is an unpleasant sensation often caused by intense or damaging stimuli such as stubbing a toe, burning a finger, putting iodine on a cut, and bumping the "funny bone."...

, insensibility
Insensibility
Insensibility is a poem written by Wilfred Owen during the First World War which explores the effect of warfare on soldiers, and the long and short term psychological effects which it has on them. The poem's title refers to the fact that the soldiers have lost the ability to feel due to the horrors...

, and invariably blisters and necrosis
Necrosis
Necrosis is the premature death of cells in living tissue. Necrosis is caused by factors external to the cell or tissue, such as infection, toxins, or trauma. This is in contrast to apoptosis, which is a naturally occurring cause of cellular death...

. Necrosis is a serious problem in cases of cobra bite as it may persist for many years after the general recovery of the victim. The following systemic symptoms may also occur: chest discomfort, fever, sore throat
Sore throat
A sore throat or throat pain is a common physical symptom usually caused by acute pharyngitis, or throat inflammation, though it also occurs in a number of other situations, such as post trauma and in diphtheria. It can cause mild to extreme pain....

, difficulty in swallowing, loss of voice, weak feeling in limbs, walking haltingly, general ache, lockjaw, and difficulty in breathing. Fatality occasionally occurs. The anti-venom is widely available and deaths are much rarer than they used to be.
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