A spitting cobra is any of several

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of cobras that can defensively spray a toxic secretion - functioning as both a

venom Venom or zootoxin is a type of toxin produced by an animal that is actively delivered through a wound by means of a bite, sting, or similar action. The toxin is delivered through a specially evolved ''venom apparatus'', such as fangs or a st ...

(that can be injected via a wound) and a

toxungen Toxungen comprises a secretion of one or more biological toxins that is transferred by one animal to the external surface of another animal via a physical delivery mechanism. Toxungens can be delivered through spitting, spraying, or smearing. As o ...

(that can be sprayed on the target surface) - from their fangs into the eyes of an attacker.

Venom

The spat toxungen is generally harmless on intact mammalian skin (although contact can result in delayed blistering of the area), but can cause permanent blindness if introduced to the eye; if left untreated it may cause

chemosis Chemosis is the swelling (or edema) of the conjunctiva. The term derives from the Greek ''chem-'' meaning chemical and ''-osis'' meaning denoting action. A chemical reaction, or in this case, a chemical reaction of the conjunctiva which is du ...

and

cornea The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber. Along with the anterior chamber and lens, the cornea refracts light, accounting for approximately two-thirds of the eye's total optical ...

l swelling. The toxungen sprays out in distinctive geometric patterns when muscles squeeze the glands to squirt it out through forward-facing holes near the tips of the fangs. Individuals of some species of spitting cobras make hissing exhalations/lunging movements of their heads when "spitting", and such actions may assist in propelling the venom, but research does not support the hypothesis that they play any major functional part except possibly enhancing the threatening effect of the behaviour. When cornered, some species "spit" their toxungen as far as . While spitting typically is their primary form of defense, all spitting cobras also can deliver their toxin as a venom by biting. Most spitting cobras' venom/toxungen is significantly cytotoxic, apart from the

neurotoxic Neurotoxicity is a form of toxicity in which a biological, chemical, or physical agent produces an adverse effect on the structure or function of the central and/or peripheral nervous system. It occurs when exposure to a substance – specificall ...

and

cardiotoxic Cardiotoxicity is the occurrence of heart dysfunction as electric or muscle damage, resulting in heart toxicity. The heart becomes weaker and is not as efficient in pumping blood. Cardiotoxicity may be caused by chemotherapy (a usual example is th ...

effects typical of other cobra species. The ability to spit likely evolved in cobras three times independently through

convergent evolution Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last com ...

. In each of these three events the venom convergently evolved to be more effective at creating pain in mammals to serve as a better deterrent, with each of the three evolutions roughly correlating with the evolution and/or arrival of early hominins.

Species

ǂ: Not a “true spitting cobra”, although these species have the ability to “eject” venom, they rarely do so and when they do use this defense, it is exceptionally rare. African cobras: * ''

Naja ashei ''Naja ashei'', commonly known as Ashe's spitting cobra or the giant spitting cobra, is a species of venomous snake in the family Elapidae. The species is native to Africa. It is the world's largest species of spitting cobra. Etymology and tax ...

'' * ''

Naja katiensis The Mali cobra (''Naja katiensis''), also called the Katian spitting cobra or West African brown spitting cobra, is a species of spitting cobra found in West Africa. Geographic Distribution This species ranges from Senegal to Cameroon, with re ...

'' * ''

Naja mossambica The Mozambique spitting cobra (''Naja mossambica'') is a highly venomous species of spitting cobra native to Africa. It is largely found in Angola, Botswana, Malawi, Mozambique, Namibia, South Africa, Tanzania, Zambia, and Zimbabwe. Taxonomy Germ ...

'' * ''

Naja nigricincta ''Naja nigricincta'' is a species of spitting cobra in the genus ''Naja'', belonging to the family Elapidae. The species is native to the deserts and drier regions of southern Africa. The species is largely nocturnal, and is often found while cro ...

'' ** '' Naja nigricincta woodi '' * '' Naja nigricollis'' * ''

Naja nubiae The Nubian spitting cobra (''Naja nubiae'') is a species of spitting cobra native to Africa. Description A relatively small spitting cobra. Maximum recorded length 148 cm. Colour and pattern: Brownish-grey overall, scale bases and skin betwe ...

'' * ''

Naja pallida The red spitting cobra (''Naja pallida'') is a species of spitting cobra native to Africa. Description This medium-sized cobra attains lengths between , but may grow to a maximum length of around in very rare cases. It is often thought of as a ...

'' Asian cobras: * ''

Naja atra The Chinese cobra (''Naja atra''), also called the Taiwan cobra, is a species of cobra in the family Elapidae, found mostly in southern China and a couple of neighboring nations and islands. It is one of the most prevalent venomous snakes in Ch ...

'' ^ǂ * ''

Naja kaouthia The monocled cobra (''Naja kaouthia''), also called monocellate cobra and Indian spitting cobra, is a venomous cobra species widespread across South and Southeast Asia and listed as Least Concern on the IUCN Red List. Taxonomy The scientific n ...

'' ^ǂ * ''

Naja sagittifera The Andaman cobra (''Naja sagittifera'') is a species of cobra endemic to the Andaman Islands of India. The name of this cobra comes from the Islands itself. The species has a very potent venom, and is capable of “spitting”, although this de ...

'' ^ǂ * ''

Naja mandalayensis The Mandalay spitting cobra (''Naja mandalayensis''), also called the Burmese spitting cobra or Mandalay cobra, is a species of spitting cobra endemic to the dry zone in central Myanmar. Etymology ''Naja mandalayensis'' was first described by her ...

'' * '' Naja philippinensis'' * '' Naja samarensis'' * ''

Naja siamensis The Indochinese spitting cobra (''Naja siamensis'') ( th, งูเห่า, pronounced: nguu hao) also called the Thai spitting cobra, Siamese spitting cobra, is a species of spitting cobra found in Southeast Asia. Description This is a medium ...

'' * ''

Naja sputatrix The Javan spitting cobra (''Naja sputatrix''), also called Indonesian cobra, is a species of cobra in the family Elapidae, found in the Lesser Sunda Islands of Indonesia, including Java, Bali, Lombok, Sumbawa, Flores, Komodo, and others. E ...

'' * '' Naja sumatrana'' Spitting snakes in other families: * '' Hemachatus haemachatus'' Some of the

Viperidae The Viperidae (vipers) are a family of snakes found in most parts of the world, except for Antarctica, Australia, Hawaii, Madagascar, and various other isolated islands. They are venomous and have long (relative to non-vipers), hinged fangs th ...

have been reported to spit occasionally.

References

* Greene, Harry W. (1997) ''Snakes: The Evolution of Mystery in Nature''. University of California Press, Berkeley and Los Angeles, California.

External links

Video
of an African red spitting cobra spraying its venom
Video
of an African red spitting cobra feeding

'Spitting Cobras' Sharp-Shooting Secrets" {{DEFAULTSORT:Spitting Cobra Elapidae Snakes of Africa Snakes of Asia