Spitting cobras

A spitting cobra is any of several species of cobras that can project venom from their fangs when defending themselves.

The spitted venom 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 and corneal swelling.

The venom 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 it has been argued that such actions 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 venom as far as 2 m (6.6 ft). While spitting typically is their primary form of defense, all spitting cobras also can deliver venom by biting. Most spitting cobras' venoms are significantly cytotoxic, apart from the neurotoxic and carditoxic effects typical of other cobra species.

African:

Asiatic:

Certain cobras, especially some Asian species that are not regarded as spitting cobras, do sometimes spit to some extent, though not as effectively as the spitters. Even some of the Viperidae have been reported to spit occasionally.

Among several viper species reported to "fling" or even "spit" venom forward in a spray when threatened, the Mangshan pitviper is particularly notable for consistent and well-aimed spraying of its venom.

The rinkhals (Hemachatus haemachatus) is another elapid species, which, while not belonging to the cobra genus Naja, is closely related and spits venom as its primary defence.

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