Venomous and Deadly!
English name: Monocled Cobra (aka “Monocellate Cobra”)
Scientific name: Naja kaouthia
Thai name: Ngu Hao Mo
Description: To 150 cm long. Reasonably thick-bodied snake with smooth scales and the typical cobra “hood” that is only spread with the snake is agitated. Head is large. Body is brown, reddish-brown, greyish-brown, or pale yellow above. In Eastern Bangkok some individuals have indistinct light bands on the body. The namesake “monocle” mark on the back of the neck is widely variable, but usually is circular. In some populations the marking may be absent. Throat is pale and the rest of the underbelly is variable, from a clouded pale coloration to the same color as the top. Underside of neck has a pair of widely separated dark dots that are visible when the snake lifts up its head and spreads its neck, as well as one or two black rings at the bottom of the throat.
Similar Species: Asian Rat Snakes (Ptyas korros and Ptyas mucosus) have larger eyes, longer tails, and lack the markings on the throat and the back of the neck.
Copperhead Racer has a larger eye, lacks the marking on the back of the neck, and has a dark line going down the front of the body and lines radiating from the eye.
Habitat: Found in a wide range of habitats, including grassland, scrubland, forest, rice paddies, swamps, and agricultural land. Can be found near human habitations, even within Bangkok. Prefers habitat associated with water. Usually stays under cover during the day.
Place in the ecosystem: Feeds on rodents, frogs, birds, and smaller snakes. Can be eaten by monitors, larger snakes, and birds of prey.
Danger to humans: The Monocled Cobra is one of the deadliest snakes in Bangkok. Under no circumstances should you handle or harass this snake, as even a young cobra can pack a deadly bite. See “Interesting Facts” for more specifics.
Conservation status and threats: No known conservation threats, as it has a wide distribution and can live close to human habitations. A small number are harvested for their skins, for snake shows, or killed out of fear. Is listed in CITES Appendix II.
Interesting facts: The Monocled Cobra is the most commonly-encountered deadly snake in Bangkok. Most bites occur when people accidentally step on or purposely try to grab a cobra. When the cobra is threatened, it will enter the typical cobra defensive reaction of lifting the front half of its body straight up, spreading out its neck, and hissing. Never approach a cobra in the defensive position. If it is not approached further, it will usually make a hasty retreat.
Cobras have a “neurotoxic” venom that is fast-acting and primarily affects the central nervous system. Initial symptoms are headache, nausea, sleepiness, and disorientation, progressing to difficulty in speech, swallowing, and walking, and eventually complete paralysis. Breathing becomes more difficult as the venom takes effect and death usually results from respiratory failure. Heart failure is also possible from the cardiotoxicity of the venom. Death can occur within 5 to 20 hours without treatment (faster if a vein is bitten), but injection of the correct antivenom will reverse the symptoms if done speedily enough. A quick trip to the nearest hospital will usually save the victim’s life. Artificial respiration may be necessary if the victim’s breathing stops before the antivenom has the chance to be administered or take full effect. Necrosis of the flesh can develop in the days following the bite if the victim survives the initial symptoms.
If you or someone you are with is bitten by a Monocled Cobra, the most important steps are to:
1) Keep the victim calm, having them lie down with the bite mark below the heart if possible.
2) Take a picture of the snake to confirm identification for the hospital.
3) Get the victim to a hospital immediately where professional treatment can take place and antivenom can be given.
4) Start rescue breathing if the victim’s breathing stops and continue until they are in the care of medical professionals.
IUCN Redlist: Naja kaouthia
Wikpedia: Moncled Cobra
The Asiatic Cobra Systematics Page
A Photographic Guide to Snakes and Other Reptiles of Peninsular Malaysia, Singapore and Thailand
A Field Guide to the Reptiles of South-East Asia
Snakes of Thailand and their Husbandry
Snake Bites and their Treatment
Michael Cota, personal communication