Indochinese Spitting Cobra

The Siamese spitting cobra (Naja siamensis) (Thai: งูเห่า, pronounced: nguu hao) also called the Indochinese spitting cobra, Thai spitting cobra and black and white spitting cobra is a species of spitting cobra found in Southeast Asia.

Description

This is a medium-sized elapid, with a more slender build compared to most other cobras within the genus Naja. The body colour of this species is variable from grey to brown to black, with white spots or stripes. The white patterning can be so prolific that it covers the majority of the snake. The highly distinctive black and white colour phase is common in central Thailand, specimens from western Thailand are mostly black, whereas individuals from elsewhere are usually brown. The hood mark can be spectacle-shaped, irregular or missing altogether, especially in adults. Adults average between 0.9 to 1.2 metres (3.0 to 3.9 ft) in length, and can potentially reach lengths of 1.6 metres (5 ft), although this is considered rare. Body mass for adults can be tends to be around 1,600 grams.

This species should not be confused with the monocled cobra (Naja kaouthia), which has similar habitat, size and appearance. Another distinguishing feature is that this species is a "true spitter"; it readily spits venom, but rather than a stream of venom as seen with many other "spitting cobras", this species ejects a "mist" rather than a "stream". Further, the reported spitting range of this species is approximately 1 metre (3.3 ft), which is the lowest range of any of the spitting cobras. Although Wüster (unpublished) reports that N. siamensis readily spits and may have a longer range, closer to 2 metres (6.6 ft), which comes out in a stream.

Scalation

There are 25-31 scale rows around the hood, 19-21 just ahead of midbody; 153-174 ventral scales, 45-54 subcaudal scales, and basal pairs are sometimes undivided.

Taxonomy

Naja siamensis is classified under the genus Naja of the family Elapidae. It was first described by Austrian-born Italian zoologist Josephus Nicolaus Laurenti in 1768. The generic name Naja is a Latinisation of the Sanskrit word nāgá (नाग), meaning "cobra". The specific epithet siamensis is derived from the word Siam or Siamese, which means "relating to or characteristic of Thailand or its people and language". This species was long confused with the monocled cobra (Naja kaouthia) and the Chinese cobra (Naja atra), and extensive variation in pattern and scalation contributed to this confusion. Detailed morphological and molecular analyses revealed it to be a distinct species during the 1990s.

Distribution and habitat

It is found in Southeast Asia, including Thailand, Cambodia, Vietnam, and Laos. May occur in eastern Myanmar but no records are known. It has been reported from Taiwan where it was released to the wild based on folklore Buddhist practices. It occupies a range of habitats including lowlands, hills, plains, and woodland. It can also be found in jungle habitat and it is sometimes attracted to human settlements because of the abundant populations of rodents in and around these areas.

Behavior and diet