| Naja melanoleuca | |
|---|---|
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Order: | Squamata |
| Suborder: | Serpentes |
| Family: | Elapidae |
| Genus: | Naja |
| Species: | N. melanoleuca |
| Binomial name | |
| Naja melanoleuca Hallowell, 1857[1] |
|
The Forest Cobra (Naja melanoleuca), also called the black cobra and black or white-lipped cobra,[2] is a species of cobra in the Elapidae family, native to Africa.
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The forest cobra is Africa's largest cobra[2] and arguably the largest of all the true cobra species (Naja) in the world.[3] The length of an average adult is 1.5 to 2.1 meters (4.9 to 6.9 ft), but they may attain lengths up to 3.1 metres (10 ft). The head of this snake is large, broad, flattened and is slightly distinct from the neck. It is a slightly depressed, tapered and moderately thick bodied snake with a slender tail that is medium in length. The body is compressed dorsoventrally and sub-cylindrical posteriorly. The forst cobra has long cervical ribs capable of expansion to form a long, wedge shaped hood when threatened. The canthus is distinct, while the snout is rounded. Its eyes are medium in size with round pupils. The dorsal scales are smooth, very shiny and glossy and are strongly oblique.[2] The colouration of this species can vary greatly. Specimens in southern Africa tend to be brown to brownish grey, while those from western Africa are banded. Most of the other forest cobras are uniform black. The ventral side is always yellow or creamy white, with dark spots seen in some specimens.[3][4]
Dorsal scales on the midbody 19-21, ventral scales 201-214, subcaudal scale is paired, subcaudal scales 63-72, analplate is single, upper labials 7 (sometimes 8), upper labials to the eye 3 + 4, preoculairs 1 (sometimes 2), postoculairs 3 (can also be 2), lower labials 8, Temporal 1+2/1+3 varying.[3]
The forest cobra occurs mainly in western Africa and central Africa.[2] It is found all the way from Senegal, Guinea-Bissau, Guinea, southeastern Mali, Sierra Leone, Liberia, Côte d'Ivoire, Burkina Faso, Ghana, Togo, Benin, Nigeria, Equatorial Guinea, Cameroon, and Gabon in western Africa to the Republic of Congo, the Democratic Republic of Congo, Central African Republic, and northern Angola in central Africa to western Kenya, Uganda, Rwanda, and Burundi in eastern Africa, and to fragmented parts of southern Africa including the Natal.[4]
Forest cobras are mainly found in the tropical and subtropical rainforest regions of west and central Africa.[5] In the fragmented parts of their range in the south and southeast, they are restricted to more open savanna forest and woodlands near the coast. They are usually found in the vicinity of water in dryer regions. The species persists in and around inhabited areas, particularly many central African towns and formerly forested regions. They are also found on fruit plantations where they live in the trees. Forest cobras are well adapted to many environments and are found from sea level to the dense mountain forests located up to 2,800 metres (9,200 ft) above sea level.[6]
The forest cobra is an agile, diurnal species that climbs well and is more aquatic than any of the other true cobras of the genus Naja.[7] It is a non-spitter and is particularly fond of water. They are often found in or around water. It will climb into low bush. The forest cobra is very alert snake, seldom cornered as it is fast-moving, but if confronted this species will raise its forebody and spread its hood and strike readily if provoked. They can be particularly aggressive when cornered. Although mainly terrestrial, they are equally at home in trees, on the ground or swimming in lakes and rivers.[6]
Forest cobras feed on a wide variety of prey, including amphibians, lizards, bird eggs, rodents, small mammals and fish.[2] [7]
Predators of the forest cobra include the honey badger (Ratel), various birds of prey such as Secretary birds, Martial eagle, and other eagles and hawks. Different species of Mongoose also prey on this species.[4]
The venom of this cobra is a postsynaptic neurotoxin. The species has a IP LD50 value of 0.32 mg/kg.[8] The SC LD50 value for this snake is 1.21 mg/kg, making it less venomous than many other cobra species, but being such a large snake when it bites, it injects a massive amount of venom.[9] The average yield of venom per bite is between 200-350 mg (dry weight), although they can yield a maximum of 500 mg.[9] Death can occur rapidly, within 30 to 120 minutes in very severe cases of envenomation. However, this is not common and the mortality rate is around 20-30%.[10]