Monocled cobra

Last updated

Monocled cobra
Monocled cobra (cropped).jpg
Monocled cobra
CITES Appendix II (CITES) [1]
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Suborder: Serpentes
Family: Elapidae
Genus: Naja
Species:
N. kaouthia
Binomial name
Naja kaouthia
Lesson, 1831
South East Asia location-Naja-kaouthia.svg
Naja kaouthia distribution

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. [1]

Contents

Taxonomy

The scientific name Naja kaouthia was proposed by René Lesson in 1831, when he described the monocled cobra as a beautiful snake that is distinct from the spectacled cobra, with 188 ventral scales and 53 pairs of caudal scales. [2]

Since then, several monocled cobras were described under different scientific names:

Several varieties of monocled cobras were described under the binomial Naja tripudians between 1895 and 1913:

In 1940, Malcolm Arthur Smith classified the monocled cobra as a subspecies of the spectacled cobra under the trinomial Naja naja kaouthia. [5] Reclassification in the 1990s further distinguished Naja kaouthia from Naja siamensis , a name commonly used in older toxinological research. [6]

Phylogenetic studies of Naja kaouthia in Thailand have demonstrated surprising variation, with one population resulting in the species becoming paraphyletic with other Asiatic cobras. [7]

Characteristics

Characteristic monocle pattern on hood Hooded Cobra - Howrah 2017-12-25 5748.JPG
Characteristic monocle pattern on hood

The monocled cobra has an O-shaped, or monocellate hood pattern, unlike that of the Indian cobra, which has the "spectacle" pattern (two circular ocelli connected by a curved line) on the rear of its hood. The elongated nuchal ribs enable a cobra to expand the anterior of the neck into a “hood”. Coloration in the young is more constant. The dorsal surface may be yellow, brown, gray, or blackish, with or without ragged or clearly defined cross bands. It can be olivaceous or brownish to black above with or without a yellow or orange-colored, O-shaped mark on the hood. It has a black spot on the lower surface of the hood on either side, and one or two black cross-bars on the belly behind it. The rest of the belly is usually the same color as the back, but paler. As age advances, the snake becomes paler, wherein the adult is brownish or olivaceous. A pair of fixed anterior fangs is present. The largest fang recorded measured 6.78 mm (0.678 cm). Fangs are moderately adapted for spitting. [8]

Adult monocled cobras reach a length of 1.35 to 1.5 m (4.4 to 4.9 ft) with a tail length of 23 cm (9.1 in). Many larger specimens have been recorded, but they are rare. Adults can reach a maximum of 2.3 m (7.5 ft) in length. [9] [10]

Scalation

The monocled cobra has 25 to 31 scales on the neck, 19 to 21 on the body, and 17 or 15 on the front of the vent. It has 164 to 197 ventral scales and 43 to 58 subcaudal scales. [9] It typically has more than one cuneate scale on each side. The shape of the frontal scale is short and square. Ventrals in males range from 170 to 192, in females from 178 to 197. Subcaudals in males range from 48 to 61, in females from 46 to 59. [8]

Distribution and habitat

The monocled cobra is distributed from India in the west through to China, Vietnam and Cambodia. It also occurs on the Malay Peninsula and is native to West Bengal, Bangladesh, Bhutan, Myanmar, Laos, Nepal, and Thailand. It can adapt to a range of habitats, from natural to anthropogenically impacted environments. It prefer habitats associated with water, such as paddy fields, swamps and mangroves, but lives also in grasslands, shrublands, forests, agricultural land at elevations of up to 1,000 m (3,300 ft) and human settlements including cities. [1]

Ecology and behaviour

Monocled cobras are terrestrial and most active at dusk. In rice-growing areas, they hide in rodent burrows in the dykes between fields and have become semi-aquatic in this type of habitat. Juveniles feed mostly on amphibians whereas adults prey on small mammals, snakes and fish. When disturbed they prefer to escape. [8] However, when threatened they will raise the anterior portions of their bodies, spread their hood, usually hiss loudly, and strike in attempt to bite and defend themselves. [10]

They are often found in tree holes and areas where rodents are plentiful. [11]

Some populations of the monocled cobra have the ability to spit venom, earning them the name "Indian spitting cobra". [12] [13]

Reproduction

This is an oviparous species. Females lay 16 to 33 eggs per clutch. Incubation periods range from 55 to 73 days. [14] Egg-laying takes place January through March. The females usually stay with the eggs. Some collaboration between males and females has been reported in Naja naja x Naja kaouthia - hybrids. [8]

Conservation status

The monocled cobra is listed on CITES Appendix II and has been assessed as Least Concern on the IUCN Red List due to its large distribution, tolerance of a broad range of habitats including anthropogenically altered environments, and its reported abundance. No major threats have been reported, and it is not thought to be undergoing a significant population decline. Monocled cobras are harvested for the wildlife trade, however, collection from the wild is minimal and not likely to cause significant population declines. [1]

Venom

The venom of the monocled cobra from three different localities were reported to exhibit different intravenous and subcutaneous median lethal dose: Thailand, 0.18-0.22 μg/g; Malaysia, 0.90-1.11 μg/g; and Vietnam, 0.90-1.00 μg/g, of mouse body weight. These results reflect the distinct difference in the lethal potency of the monocled cobra and response to antivenom neutralization. [15] The major toxic components in cobra venoms are postsynaptic neurotoxins, which block the nerve transmission by binding specifically to the nicotinic acetylcholine receptor, leading to flaccid paralysis and even death by respiratory failure. The major α-neurotoxin in the monocled cobra's venom is a long neurotoxin, α-cobratoxin; the minor α-neurotoxin is different from cobrotoxin in one residue. [16] The neurotoxins of this particular species are weak. [17] The venom of this species also contains myotoxins and cardiotoxins. [18] [19]

In case of intravenous injection the LD50 tested in mice is 0.373 mg/kg, and 0.225 mg/kg in case of intraperitoneal injection. [20] The average venom yield per bite is approximately 263 mg dry weight. [21]

The monocled cobra causes the highest fatality due to snake venom poisoning in Thailand. [22] Envenomation usually presents predominantly with extensive local necrosis and systemic manifestations to a lesser degree. Drowsiness, neurological and neuromuscular symptoms will usually manifest earliest; hypotension, flushing of the face, warm skin, and pain around bite site typically manifest within one to four hours following the bite; paralysis, ventilatory failure or death could ensue rapidly, possibly as early as 60 minutes in very severe cases of envenomation. However, the presence of fang marks does not always imply that envenomation actually occurred. [23]

See also

Related Research Articles

<span class="mw-page-title-main">King cobra</span> Venomous snake species from Asia

The king cobra is a venomous snake endemic to Asia. The sole member of the genus Ophiophagus, it is not taxonomically a true cobra, despite its common name and some resemblance. With an average length of 3.18 to 4 m and a record length of 5.85 m (19.2 ft), it is the world's longest venomous snake. The species has diversified colouration across habitats, from black with white stripes to unbroken brownish grey. The king cobra is widely distributed albeit not commonly seen, with a range spanning from the Indian Subcontinent through Southeastern Asia to Southern China. It preys chiefly on other snakes, including those of its own kind. This is the only ophidian that constructs an above-ground nest for its eggs, which are purposefully and meticulously gathered and protected by the female throughout the incubation period.

<span class="mw-page-title-main">Elapidae</span> Family of venomous snakes

Elapidae is a family of snakes characterized by their permanently erect fangs at the front of the mouth. Most elapids are venomous, with the exception of the genus Emydocephalus. Many members of this family exhibit a threat display of rearing upwards while spreading out a neck flap. Elapids are endemic to tropical and subtropical regions around the world, with terrestrial forms in Asia, Australia, Africa, and the Americas and marine forms in the Pacific and Indian Oceans. Members of the family have a wide range of sizes, from the 18 cm (7.1 in) white-lipped snake to the 5.85 m king cobra. Most species have neurotoxic venom that is channeled by their hollow fangs, and some may contain other toxic components in various proportions. The family includes 55 genera with around 360 species and over 170 subspecies.

<span class="mw-page-title-main">Spitting cobra</span> Common name for several snakes

A ”spitting” cobra is any of several species of cobra that can intentionally, defensively shoot their venom directly from their fangs. This substance has two functions, with the first being as venom that can be absorbed via the victim’s eyes, mouth, or nose, and secondly as a toxungen, which can be sprayed on the target surface. Their ability to target and shoot venom is utilised in several different ways, self-defense being the most common instance. Studies have shown that the targets are far from random; rather, spitting cobras consciously take aim, directing their spray as close as possible to the eyes and face of an aggressor.

<span class="mw-page-title-main">Indian cobra</span> Species of snake

The Indian cobra, also known commonly as the spectacled cobra, Asian cobra, or binocellate cobra, is a species of cobra, a venomous snake in the family Elapidae. The species is native to the Indian subcontinent, and is a member of the "big four" species that are responsible for the most snakebite cases in India.

<span class="mw-page-title-main">Caspian cobra</span> Species of snake

The Caspian cobra, also called the Central Asian cobra or Russian cobra, is a species of highly venomous snake in the family Elapidae. The species is endemic to Central Asia. First described by Karl Eichwald, a German physician, in 1831, it was for many years considered to be a subspecies of the Naja naja until genetic analysis revealed it to be a distinct species.

<span class="mw-page-title-main">Philippine cobra</span> Species of snake

The Philippine cobra also called Philippine spitting cobra or northern Philippine cobra, is a stocky, highly venomous species of spitting cobra native to the northern regions of the Philippines. The Philippine cobra is called ulupong in Tagalog, carasaen in Ilocano.

<i>Naja</i> Genus of snakes

Naja is a genus of venomous elapid snakes commonly known as cobras. Members of the genus Naja are the most widespread and the most widely recognized as "true" cobras. Various species occur in regions throughout Africa, Southwest Asia, South Asia, and Southeast Asia. Several other elapid species are also called "cobras", such as the king cobra and the rinkhals, but neither is a true cobra, in that they do not belong to the genus Naja, but instead each belong to monotypic genera Hemachatus and Ophiophagus.

<span class="mw-page-title-main">Many-banded snake</span> Species of snake

The many-banded snake, also known commonly as the burrowing cobra, is a species of venomous snake in the family Elapidae. The species is native to Central Africa. There are three recognized subspecies.

<span class="mw-page-title-main">Chinese cobra</span> Species of snake

The Chinese cobra, Guizhou spitting cobra, or 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 China, which has caused many snakebite incidents to humans.

<span class="mw-page-title-main">Egyptian cobra</span> Species of reptile (snake)

The Egyptian cobra is one of the most venomous species of snakes in North Africa, and has caused many snakebite incidents to humans. It averages roughly 1.4 metres (4.6 ft), with the longest recorded specimen measuring 2.59 metres (8.5 ft).

<i>Naja ashei</i> Species of snake

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.

<span class="mw-page-title-main">Indochinese spitting cobra</span> Species of snake

The Indochinese spitting cobra also called the Thai spitting cobra, black and white spitting cobra, Siamese spitting cobra, is a species of spitting cobra found in Southeast Asia.

<span class="mw-page-title-main">Forest cobra</span> Species of snake

The forest cobra, also commonly called the black cobra and the black and white-lipped cobra, is a species of highly venomous snake in the family Elapidae. The species is native to Africa, mostly the central and western parts of the continent. It is the largest true cobra species with a record length of 3.2 metres.

<span class="mw-page-title-main">Equatorial spitting cobra</span> Species of snake

The Equatorial spitting cobra also called the Malayan spitting cobra, golden spitting cobra, Sumatran spitting cobra, or Palawan spitting cobra, is a species of spitting cobra found in Southeast Asia.

<span class="mw-page-title-main">Anchieta's cobra</span> Species of snake

Anchieta's cobra, sometimes referred to as the Angolan cobra, is a species of venomous snake in the family Elapidae. The species is native to Southern Africa.

<span class="mw-page-title-main">Mandalay spitting cobra</span> Species of snake

The Mandalay spitting cobra, also called the Burmese spitting cobra or Mandalay cobra, is a species of spitting cobra endemic to the Dry Zone in central Myanmar.

<span class="mw-page-title-main">Andaman cobra</span> Species of snake

The Andaman cobra or Andaman spitting cobra 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 defensive behavior is very rare and the aim is poor and not as efficient as “true spitting cobras”.

<span class="mw-page-title-main">Javan spitting cobra</span> Species of snake

The Javan spitting cobra, also called Indonesian cobra or Komodo spitting 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.

The brown banded cobra is a species of venomous cobra, endemic to Southeast Asia. It was considered to be a part of Naja kaouthia until genetic studies conducted in 2022 rendered it a separate species.

References

  1. 1 2 3 4 5 Stuart, B.; Wogan, G. (2012). "Naja kaouthia". IUCN Red List of Threatened Species . 2012: e.T177487A1488122. doi: 10.2305/IUCN.UK.2012-1.RLTS.T177487A1488122.en . Retrieved 29 January 2022.
  2. ↑ Lesson, R.-P. (1831). "Catalogue des Reptiles qui font partie d'une Collection zoologique recueillie dans l'Inde continental ou en Afrique, et apportée en France par M. Lamare-Piqout. Catalogue dressé (juillet 1831)". Bulletin des Sciences Naturelles et de Géologie (XXV): 119–123.
  3. ↑ Gray, J. E. (1834). "Cobra Capella". Illustrations of Indian zoology chiefly selected from the collection of Maj.-Gen. Hardwicke. Vol. II. p. Plate 78.
  4. ↑ Cantor, T. (1839). "Naja larvata". Proceedings of the Zoological Society of London. VII: 32–33.
  5. ↑ Smith, M. A. (1940). "Naja naja kaouthia". Records of the Indian Museum. XLII: 485.
  6. ↑ Wüster, W. (1996). "Taxonomic changes and toxinology: Systematic revisions of the Asiatic cobras (Naja naja species complex)". Toxicon. 34 (4): 399–406. doi:10.1016/0041-0101(95)00139-5. PMID   8735239.
  7. ↑ Ratnarathorn, N.; Harnyuttanakorn, P.; Chanhome, L.; Evans, S. E.; Day, J. J. (2019). "Geographical differentiation and cryptic diversity in the monocled cobra, Naja kaouthia (Elapidae), from Thailand". Zoologica Scripta. 48 (6): 711–726. doi:10.1111/zsc.12378. S2CID   201199120.
  8. 1 2 3 4 Wüster, W. (1998). "The cobras of the genus Naja in India" (PDF). Hamadryad. 23 (1): 15–32.
  9. 1 2 Smith, M. A. (1943). "Naja naja kaouthia". The Fauna of British India, Ceylon and Burma, Including the Whole of the Indo-Chinese Sub-Region. Reptilia and Amphibia. Vol. III (Serpentes). London: Taylor and Francis. pp. 428–432.
  10. 1 2 Chanhome, L.; Cox, M. J.; Vasaruchaponga, T.; Chaiyabutra, N. S. (2011). "Characterization of venomous snakes of Thailand". Asian Biomedicine. 5 (3): 311–328.
  11. ↑ "Naja kaouthia: General Details and Information". WCH Clinical Toxinology Resource. University of Adelaide. Retrieved 3 February 2012.
  12. ↑ Wuster, Wolfgang; Thorpe, Roger S. (1992). "Dentitional phenomena in cobra revisited: spitting and fang structure in the Asiatic species of Naja (Serpentes: Elapidae)" (PDF). Herpetologica. 48 (4): 424–434.
  13. ↑ Santra, Vishal; Wüster, Wolfgang (2017). "Naja kaouthia behavior/spitting" (PDF). Herpetological Review. 48 (2): 455.
  14. ↑ Chanhome, L; Jintkune, P.; Wilde, H.; Cox, M. J. (2001). "Venomous snake husbandry in Thailand". Wilderness and Environmental Medicine. 12 (1): 17–23. doi: 10.1580/1080-6032(2001)012[0017:vshit]2.0.co;2 . PMID   11294550.
  15. ↑ Tan, K.Y.; Tan, C.H.; Fung, S.Y.; Tan, N.H. (2015). "Venomics, lethality and neutralization of Naja kaouthia (monocled cobra) venoms from three different geographical regions of Southeast Asia". Journal of Proteomics. 120: 105–125. doi:10.1016/j.jprot.2015.02.012. PMID   25748141.
  16. ↑ Wei, J.-F.; Lü, Q.-M.; Jin, Y.; Li, D.-S.; Xiong, Y.-L.; Wang, W.-Y. (2003). "α-Neurotoxins of Naja atra and Naja kaouthia Snakes in Different Regions". Acta Biochimica et Biophysica Sinica. 35 (8): 683–688. PMID   12897961.
  17. ↑ Ogay, A.; Rzhevskya, D.I.; Murasheva, A.N.; Tsetlinb, V.I.; Utkin, Y.N. (2005). "Weak neurotoxin from Naja kaouthia cobra venom affects haemodynamic regulation by acting on acetylcholine receptors". Toxicon. 45 (1): 93–99. doi:10.1016/j.toxicon.2004.09.014. PMID   15581687.
  18. ↑ Mahanta, M.; Mukherjee, A.K. (2001). "Neutralisation of lethality, myotoxicity and toxic enzymes of Naja kaouthia venom by Mimosa pudica root extracts". Journal of Ethnopharmacology. 75 (1): 55–60. doi:10.1016/S0378-8741(00)00373-1. PMID   11282444.
  19. ↑ Fletcher, J. E.; Jiang, M.-S.; Gong, Q.-H.; Yudkowsky, M.L.; Wieland, S.J. (1991). "Effects of a cardiotoxin from Naja kaouthia venom on skeletal muscle: Involvement of calcium-induced calcium release, sodium ion currents and phospholipases A2 and C". Toxicon. 29 (12): 1489–1500. doi:10.1016/0041-0101(91)90005-C. PMID   1666202.
  20. ↑ Fry, B.G. "LD50 Menu". Australian Venom Research Unit. University of Queensland. Archived from the original on 13 April 2012. Retrieved 25 December 2011.
  21. ↑ Engelmann, W.-E. (1981). Snakes: Biology, Behavior, and Relationship to Man. Leipzig; English version NY, USA: Leipzig Publishing; English version published by Exeter Books (1982). p. 51. ISBN   978-0-89673-110-3.
  22. ↑ Pratanaphon, R.; Akesowan, S.; Khow, O.; Sriprapat, S.; Ratanabanangkoon, K. (1997). "Production of highly potent horse antivenom against the Thai cobra (Naja kaouthia)". Vaccine. 15 (14): 1523–1528. doi:10.1016/S0264-410X(97)00098-4. PMID   9330463.
  23. ↑ Davidson, T. "Snakebite Protocols: Summary for Human Bite by Monocellate Cobra (Naja naja kaouthia)". Archived from the original on 2012-12-03. Retrieved 2011-11-10.

Further reading

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.