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| The King Cobra or Hamadryad, Ophiophagus hannah (Cantor, 1836). King Cobras are the largest venomous snake, they range from northern India eastward to tropical China and the Philippines, and southward through Indochina and Indonesia. The hamadryad is diurnal, often associated with the forest along the edges streams. They are usually terrestrial, but do not hesitate to forage into shrubs or trees. Most specimens are in the 3-4 m range, but the record size for this snake is about 5.85 m. The large size of the hamadryad makes it well suited for snake shows and in northern Thailand's Khon Kaen Province the village of Ban Kok Sa-nga is known as King Cobra Village. The village claims to raise hamadryads as pets and put on shows for tourists. As with many snake charmers the village snake handlers also sell herbal medicines. Females lay clutches of 20-51 eggs in a nest made of vegetation that the female constructs. The female guards the eggs for 60-80 days. Hatchlings from at least populations have a strikingly vivid pattern of alternating black and yellow rings. Aposematic coloring, and coloring remarkably similar to that of the Mangrove Snake, Boiga dendrophila. The Hamadryad feeds mostly upon other snakes. |
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| Monocellate Cobra, Naja kaouthia (Lesson, 1831). Top two photos are of a captive animal from Thailand. The bottom photo was taken at the King Cobra Village in Khon Kaen Province, Thailand and it is most likely this species (however, this species is very difficult to distinguish from N. siamensis, see below). Adults may reach 2.3 m. However, specimens over 1.5 m are rather uncommon. This species occurs from northeast India and Myanmar east into Thailand and tropical China, as well as most of Indochina. It feeds upon a variety of vertebrates. It is crepuscular and diurnal, occasionally basking during cooler weather. It (as well as other cobras) is hunted for its value in Chinese folk medicine, its blood, gall bladder, and other tissues are believed to improve eye sight and erectile dysfunction, as well as other ailments. |
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The Spectacled Cobra, Naja naja (Linnaeus, 1758). This is a South Asian snake, inhabiting Pakistan, India, Nepal. Bangladesh and Sri Lanka. Its pattern is highly variable and because of this it was long confused with Southeast Asian taxa. Adults may exceed 2 m, but most are less than 1.5 m. Like most cobras it is crepuscular (active at dusk and dawn) and diurnal (active during the day). But it may also be active at night. It uses a variety of habitats including agroecosystems and urbanized areas where rats are abundant. Females lay 12-30 eggs between April and July (the time may be correlated with latitude). Rice cultivation has undoubtedly increased the habitat for this snake, it uses holes in the banks of the dikes used to control water flow and rice cultivation has also created more favorable habitats for rats. The venom of this snake is quite toxic and the symptoms usually appear soon (<10-30 minutes) after the bite. Naja naja venom effects the nervous system (drooping eyelids, difficulty speaking and swallowing, gasping for air, and weakness) but it will also cause necrosis (damage to tissues around the bite site due to digestive-like enzymes). Nagapanchami or the Serpent Festival occurs in India generally in August after the monsoon rains. It is then that the full impact of Cobra power is manifest. Throughout the country Cobras are either brought into the villages and fed, or effigies of the snake are anointed and worshipped. Rarely has it ever been recorded that a fatality has occurred from snakebite during this occasion; the Cobras appear to sense they are being revered. |
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Indo-Chinese Spitting Cobra, Naja siamensis Laurenti, 1768. Photographed at the Red Cross Venom Unit, Bangkok. Adults reach 1.6 m. This snake is very difficult to distinguish from N. kaouthia on the basis of morphology (the ventral counts however, will distinguish them). None the less they are distinct species (Wuster and Thorpe, 1994 Experientia, 50: 75-79). Naja siamensis will spit its venom, where as N. kaouthia will rarely, if ever spit. Spitting venom is a characteristic of a number of different African and Asian cobras and the modifications to the venom delivery system of spitters is quite minimal. Species capable of spitting venom have a reduced orifice on the fang. Thus, by restricting the size of the opening the venom flows through, the snake increases the fluid pressure and is able to "spit" its venom a distance of at least a few meters. Most spitting cobras aim for the eyes of the animal that is harassing them. Thus, temporarily blinding the potential predator so that the snake can escape. Spitting is a defensive behavior, not an offensive behavior. Goring Jones (1900 Journal of the Bombay Natural History Society 13:376.) provided what may be the first description of “spitting venom” from a cobra near Mandalay, Burma (now Myanmar).
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| Cobras are very distinctive snakes when their hood is dilated by the anterior ribs, otherwise they appear to be just another colubroid snake. Their heads are not particularly distinct from the neck, they have round pupils, and the large, plate-like head scales make them similar in appearance to other colubroids, but they are missing the loreal scale (a condition found in some other snakes). Currently there are about 21 species in the genus Naja which is distributed from Africa and the Middle East eastward to the Philippines and southward into Indonesia. Only one species of king cobra, Ophiophagus hannah, is currently recognized, but that one widespread species will most likely be divided into several species. Cobras are the ultimate snakes for the snake charmer and snake shows, they are easily recognized when the hood is spread, their reputation for being dangerous is legendary, they tend to strike down from a raised hood display position, and when they try to escape they travel a straight path. |