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Caspian cobra

November 02, 2023

The Caspian cobra (Naja oxiana), also called the Central Asian cobra, ladle snake,[5] Oxus cobra, or Russian cobra, is a species of venomous snake in the family Elapidae. The species is endemic to Central Asia. Described by Karl Eichwald in 1831, it was for many years considered a subspecies of the Indian cobra until genetic analysis revealed it to be a distinct species.

Caspian cobra
CITES Appendix II (CITES)[2]
Scientific classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Suborder: Serpentes
Family: Elapidae
Genus: Naja
Species:
N. oxiana
Binomial name
Naja oxiana
(Eichwald, 1831)[3]
Naja oxiana distribution
Synonyms[4]
  • Naja naja subsp. oxiana (Eichwald, 1831)
  • Naja tripudians var. caeca Boulenger, 1896
  • Tomyris oxiana Eichwald, 1831

Taxonomy edit

Baltic German naturalist Karl Eichwald described the Caspian cobra originally as Tomyris oxiana in 1831.[6] Russian naturalist Alexander Strauch placed it in the genus Naja in 1868. The generic name naja is a Latinisation of the Sanskrit word nāgá (नाग) meaning "cobra". The specific epithet oxiana is derived from the word Ōxus in Latin or Ὦξος (Ôxos) in Greek,[7] and refers to the ancient name of the river Amu Darya which flows along Afghanistan`s northern border separating it from Tajikistan and Uzbekistan before turning northwest into Turkmenistan and flows from there into the southern remnants of the Aral Sea in Central Asia (Transoxiana), where this species occurs. For most of the twentieth century, all Asiatic cobras were considered to be subspecies of the Indian cobra (Naja naja); during this period, the subspecific names N. naja oxiana and N. naja caeca were applied to plain-scaled populations of N. naja from the north of India as well as populations corresponding to the Caspian cobra. Highly variable coloration and size within individual species made classification difficult until the advent of genetic analysis.[8]

A mitochondrial DNA study of Asiatic cobras in the subgenus Naja showed the Caspian cobra diverged from a lineage that gave rise to the monocled cobra (Naja kaouthia) and the Andaman cobra (Naja sagittifera) around 3.21 million years ago. The species itself appears to be genetically homogeneous despite population separation caused by the Hindu Kush mountains; this suggests a recent rapid range expansion.[9]

Naja
(Naja)

Description edit

 
A Caspian cobra

Naja oxiana is medium in length, a heavy-bodied snake with long cervical ribs capable of expansion to form a hood. Anteriorly, the body is depressed dorsoventrally, and posteriorly it is subcylindrical. This species is similar in size to Naja naja, averaging about 1 to 1.4 m (3.3 to 4.6 ft)[10][11] in total length (including tail) and rarely reaches lengths over 1.7 m (5.6 ft).[10][12] The head is elliptical, depressed, and slightly distinct from the neck, with a short, rounded snout and large nostrils. The eye is medium in size with a round pupil. The dorsal scales are smooth and strongly oblique, with the outer two or three scale rows larger than the remainder.[13] The hood of N. oxiana has an elongated, gradually tapering shape in contrast to the more ovoid hoods of some other Naja species (Naja naja or Naja kaouthia).[11] Juveniles tend to be pale, with a faded appearance. Juveniles have noticeable dark and light cross-bands of approximately equal width around the body. Adults of this species are completely light to chocolate brown or yellowish, with some specimens retaining traces of juvenile banding, especially the first few dark ventral bands. This species has no hood marks and no lateral throat spots.[12]

Confusions may exist with the Indian cobra (Naja naja), as specimens without a hood mark are usually confused with this species, and these two species coexist in Pakistan and northern India. They're also both the only true non-spitting cobras in Asia.[14] The Caspian cobra (Naja oxiana) is never fully black, although some specimens may be quite dark. The Caspian cobra (N. oxiana) normally has several dark bands under the throat, whereas in the black phase of the Indian cobra (N. naja) from Pakistan, almost the entire throat is black.[15] The hood has an elongate, gradually tapering shape in contrast to the more ovoid hoods of some other Naja species (Naja naja or Naja kaouthia).[11]

Scalation edit

See also: Snake scale § Nomenclature of scales

The number and pattern of scales on a snake's body are a key element of identification to species level.[16] Naja oxiana has 23 to 27 (usually 25) dorsal scale rows at the hood, 19–23 (usually 21) just ahead of midbody, 191–210 ventrals, and 57–71 paired subcaudals; cuneate scales (small angular scales between the labials) are often absent.[12]

Distribution and habitat edit

Naja oxiana occurs in the Transcaspian region. It is found throughout Turkmenistan, Uzbekistan, Kyrgyzstan, southwestern Tajikistan, the Fergana Valley, north and east Afghanistan, northeastern Iran. In Iran, it occurs from East Azerbaijan Province, southern half of Ardabil Province to the Provinces of Zanjan and Tehran all the way to the eastern half of both Isfahan and Yazd Provinces, as well the northeastern parts of Kerman Province, northern part of Sistan and Baluchistan Province, throughout the Provinces of Semnan, Mazandaran, and Golestan the entire former Province of Khorasan, which was split into three separate provinces post-2004). Although this species is found throughout much of Pakistan, from Balochistan and Sindh to Gilgit-Baltistan and Azad Kashmir,[13] it is far more common in the northern half of Pakistan. This species has also been observed in far northwest India in Jammu and Kashmir (union territory) and also been observed in the state of Himachal Pradesh. It's also highly suspected to have occurred in Ladakh,[12] and in the Indian state of Punjab.[13][12] There is also anecdotal evidence of it ranging as far north as Kazakhstan's southern border with Uzbekistan, according to Brian Hayes, a biochemical engineer with the United States Threat Reduction Agency. Hayes led an expedition to Vozrozhdeniye Island in the Aral Sea in the summer of 2002 to bury anthrax on the island, which is located in the Aral Sea and is split between Uzbekistan and Kazakhstan, with the northern half of the island belonging to Kazakhstan. Mr. Hayes mentioned a 2.4 m (7.9 ft) long cobra that was observed and shot near the tents where the staff lived. “In all, we had run-ins with about 25 poisonous snakes”.[17] The only "cobra” species which occurs in this region is Naja oxiana, so any “cobra” observed in Kazakhstan would likely be of this species.[citation needed]

Naja oxiana is often found in arid and semiarid, rocky or stony, shrub- or scrub-covered foothills[13] at elevations up to about 3,000 m (9,800 ft) above sea level. This is also the westernmost species of Asiatic cobra.[18]

Ecology edit

Behavior edit

Naja oxiana tends to avoid humans as much as it can, but it can become fiercely defensive when threatened or cornered, and even juveniles tend to be very aggressive. When cornered and provoked, it is liable to spread its hood, hiss, sway from side to side and strike repeatedly; however, it can not spit venom. This terrestrial species is mainly diurnal, but it may be crepuscular and nocturnal in some parts of its range during the hottest month (July). Caspian cobras are good climbers, and able swimmers. The Caspian cobra is often found in water and seldom found too far away from it.[13][11] Quick-moving and agile, this species lives in holes in embankments or trees.[18]

Diet edit

The Caspian Cobra feeds mostly on small mammals, amphibians, occasionally fish, birds and their eggs. It also reportedly feeds on other snakes.[19][13][11]

Venom edit

Composition edit

The Caspian cobra is considered to be the most venomous species of cobra in the world. Several different toxinological studies suggest this, including one particular study reported in the Indian Journal of Experimental Biology in 1992.[20] A study analyzing the toxic fractions of Naja oxiana venom from Iran indicated that toxic fractions constituted 78% by weight of crude venom of this species,[21] similar to Naja naja.[22] The toxic fractions were composed of three protein families, among which the 3FTs was dominant, similar to all other Naja species. The venom of N. oxiana was rich in short neurotoxins, which make up the majority of crude venom.[21] A number of small nonenzymatic proteins are found in the venom, including neurotoxins and members of the cytotoxin family,[23] which have been shown to cause cell death through damage to lysosomes.[24]

In addition to nonenzymatic proteins, the venom also contains nucleases, which cause tissue damage at the site of the bite and may also potentiate systemic toxicity by releasing free purines in situ.[25] A ribonuclease isolated and purified from Caspian cobra venom, ribonuclease V1, is commonly used as a laboratory reagent in molecular biology experiments due to its unusual ability to break down structured RNA.[26]

N. oxiana is one of the most dangerous snakes belonging to the elapidae family. Two main toxins as well as a number of minor components and three basic polypeptides similar to cardiotoxins (CTXs) and cytotoxins were isolated from the crude venom of this species, with acute effects on cardiac system during the first few hours post-envenomation. There are a few case reports of acute myocardial infarction (MI) following bites from elapids. At least one case of myocardial infarction following a bite from a Caspian cobra is recorded.[27]

Toxic effects edit

Naja oxiana is regarded as the most dangerous snake in Central Asia and is one of the venomous snakes with a high mortality rate.[28] It is one of the most dangerous elapid species in the world.[27] A bite from this species will cause severe pain and swelling at the site of the bite, along with the rapid onset of prominent neurotoxicity. Weakness, drowsiness, ataxia, hypotension, and paralysis of the throat and limbs may appear in less than one hour after the bite. In a study, the first signs and symptoms of envenomation appeared within 15 minutes post-envenomation. Without medical treatment, symptoms rapidly worsen and death can occur soon after a bite due to respiratory failure.[18] As with all species of cobra, there is great variation in venom toxicity and composition based on diet and geographical location. Venom toxicity is highest (least lethal) among specimens in the eastern parts of their geographical range (Indian and Pakistani specimens) with a value of around 0.2 mg/kg. Specimens from Iran, Uzbekistan, northeastern Afghanistan, and Turkmenistan can have considerably more potent venoms. The onset of symptoms is rapid and are extremely painful. Without treatment, death is likely and depending on the nature of the bite, the potency of the venom and the amount, death can occur in as little as 45 minutes or may be prolonged for up to 24 hours.[27]

According to a 2019 study by Kazemi-Lomedasht et al., the murine LD50 via subcutaneous injection value for Naja oxiana (Iranian specimens) was estimated to be 0.14 mg/kg (0.067-0.21 mg/kg)[28] more potent than the sympatric Pakistani Naja naja karachiensis (0.22 mg/kg), the Thai Naja kaouthia (0.2 mg/kg), and Naja philippinensis at 0.18 mg/kg (0.11-0.3 mg/kg)[29] An older study by Zug et al listed a LD50 value of 0.2 mg/kg from Pakistani and Indian specimens.[30] Average venom yield per bite for this species is between 75 and 125 mg (dry weight),[13] while in other parts of its distribution venom yield average is between 150 and 225 mg (dry weight).[28] The highest single bite yields are between 590[31] and 784 mg (dry weight).[28] The crude venom of N. oxiana has a lowest published lethal dose (LCLo) of 0.005 mg/kg, the lowest among all cobra species, derived from an individual case of poisoning by intracerebroventricular injection.[32]

Between 1979 and 1987, 136 confirmed bites were attributed to this species in the former Soviet Union. Of the 136, 121 received antivenom, and only 8 died (6.6%). Of the 15 who did not receive antivenom, 11 died (an untreated mortality rate of 73%).[33][34] In Iran, where the Caspian cobra is widespread, it is responsible for the highest number of deaths due to snakebite in the country. The Levant viper, Saw-scaled viper, and the Persian horned viper are responsible for more snakebite incidents, but they have a lower mortality rate compared to N. oxiana. Multiplying habitat suitability models of the four snakes showed that the northeast of Iran (west of Khorasan-e-Razavi province) has the highest snakebite risk in the country. In addition, villages that were at risk of envenoming from the four snakes were identified. Results revealed that 51,112 villages are at risk of envenoming from M. lebetinus (Levant viper), 30,339 from E. carinatus (saw-scaled viper), 51,657 from P. persicus (Persian horned viper) and 12,124 from N. oxiana (Caspian cobra). A study reported 53,787 cases of bites by venomous snakes between 2002 and 2011 in Iran, with the highest rate of snakebite incidents being found in provinces in the south and southwest of Iran.[35] Out of the 53,787 cases of snake bites which were reported to medical centers in Iran, only 118 were correctly identified as bites by this species. In total there were 67 deaths, 51 of which were due to N. oxiana. Out of the 51 bites, 46 didn't receive medical treatment. One 10-year-old male died en route to the closest hospital ~35 minutes post-envenomation. Five were treated with antivenom, but succumbed to the venom regardless of the fact (~7% mortality despite treatment). Untreated mortality rates seem to be particularly high for a species within the genus Naja, at around ~80%.[35][36][5] In Pakistan, it is responsible for high rates of snakebites that result in mortality.[18] Reliable figures on incidence, morbidity and mortality are limited but almost 40,000 biting cases are reported annually which result in up to 8,200 fatalities in one study. An estimate of annual mortality rate in Pakistan is around 1.9 per 100,000 population. In one survey, it was reported that out of 5,337 envenomed patients, 57% were cobra victims and the remaining rest of 35% were bitten by kraits and vipers. Of the 5,337 envenomed patients, there were 3,064 cobra (N. naja and N. oxiana) victims. Out of the 3,064 bitten by cobras (841 correctly identified as N. naja, and 384 were correctly identified as N. oxiana). There were 78 untreated cases, of which 64 were fatal (82%), much higher than untreated cases for N. naja (33.6%).[31][37] A woman bitten by this species in northwestern Pakistan suffered prominent neurotoxicity and died while en route to the closest hospital nearly 50 minutes after envenomation (death occurred 45–50 minutes post envenomation).[36] Antivenom is not as effective for envenomation by this species as it is for other Asiatic cobras within the same region, like the Indian cobra (N. naja), and due to the dangerous toxicity of this species' venom, massive amounts of antivenom are often required for patients. As a result, a monovalent antivenom serum is being developed by the Razi Vaccine and Serum Research Institute in Iran. Response to treatment with antivenom is generally poor among patients, so mechanical ventilation and endotracheal intubation is required. As a result, mortality among those treated for N. oxiana envenomation is still relatively high (up to 30%) compared to all other species of cobra (<1%).[31]

References edit

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  14. ^ Wüster, W; Thorpe, RS (December 1992). "Dentitional Phenomena in Cobras Revisited: Spitting and Fang Structure in the Asiatic Species of Naja (Serpentes: Elapidae)". Herpetologica. 48 (4): 424–434. JSTOR 3892862. Retrieved 14 July 2021.
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Further reading edit

  • Wüster, Wolfgang (1993). "A century of confusion: Asiatic cobras revisited". Vivarium. 4 (4): 14–18.
  • Wüster, Wolfgang; Thorpe, Roger S. (1991). "Asiatic cobras: Systematics and snakebite". Experientia. 47 (2): 205–209. doi:10.1007/BF01945429. PMID 2001726. S2CID 26579314.
  • Wüster W, Thorpe RS (1992). "Asiatic Cobras: Population Systematics of the Naja naja Species Complex (Serpentes: Elapidae) in India and Central Asia". Herpetologica. 48 (1): 69–85. JSTOR 3892921.
  • Wüster W (1998). "The cobras of the genus Naja in India". Hamadryad. 23 (1): 15–32.

External links edit

  • Naja oxiana at the Reptarium.cz Reptile Database

November 02, 2023
caspian, cobra, naja, oxiana, also, called, central, asian, cobra, ladle, snake, oxus, cobra, russian, cobra, species, venomous, snake, family, elapidae, species, endemic, central, asia, described, karl, eichwald, 1831, many, years, considered, subspecies, ind. The Caspian cobra Naja oxiana also called the Central Asian cobra ladle snake 5 Oxus cobra or Russian cobra is a species of venomous snake in the family Elapidae The species is endemic to Central Asia Described by Karl Eichwald in 1831 it was for many years considered a subspecies of the Indian cobra until genetic analysis revealed it to be a distinct species Caspian cobraConservation statusNear Threatened IUCN 3 1 1 CITES Appendix II CITES 2 Scientific classificationDomain EukaryotaKingdom AnimaliaPhylum ChordataClass ReptiliaOrder SquamataSuborder SerpentesFamily ElapidaeGenus NajaSpecies N oxianaBinomial nameNaja oxiana Eichwald 1831 3 Naja oxiana distributionSynonyms 4 Naja naja subsp oxiana Eichwald 1831 Naja tripudians var caeca Boulenger 1896 Tomyris oxiana Eichwald 1831 Contents 1 Taxonomy 2 Description 2 1 Scalation 3 Distribution and habitat 4 Ecology 4 1 Behavior 4 2 Diet 5 Venom 5 1 Composition 5 2 Toxic effects 6 References 7 Further reading 8 External linksTaxonomy editBaltic German naturalist Karl Eichwald described the Caspian cobra originally as Tomyris oxiana in 1831 6 Russian naturalist Alexander Strauch placed it in the genus Naja in 1868 The generic name naja is a Latinisation of the Sanskrit word naga न ग meaning cobra The specific epithet oxiana is derived from the word Ōxus in Latin or Ὦ3os Oxos in Greek 7 and refers to the ancient name of the river Amu Darya which flows along Afghanistan s northern border separating it from Tajikistan and Uzbekistan before turning northwest into Turkmenistan and flows from there into the southern remnants of the Aral Sea in Central Asia Transoxiana where this species occurs For most of the twentieth century all Asiatic cobras were considered to be subspecies of the Indian cobra Naja naja during this period the subspecific names N naja oxiana and N naja caeca were applied to plain scaled populations of N naja from the north of India as well as populations corresponding to the Caspian cobra Highly variable coloration and size within individual species made classification difficult until the advent of genetic analysis 8 A mitochondrial DNA study of Asiatic cobras in the subgenus Naja showed the Caspian cobra diverged from a lineage that gave rise to the monocled cobra Naja kaouthia and the Andaman cobra Naja sagittifera around 3 21 million years ago The species itself appears to be genetically homogeneous despite population separation caused by the Hindu Kush mountains this suggests a recent rapid range expansion 9 Naja Naja Naja Naja najaNaja Naja kaouthiaNaja Naja atraNaja Naja sagittiferaNaja Naja oxianaNaja Naja sputatrixNaja Naja samarensisNaja Naja philippinensisNaja Naja mandalayensisNaja Naja sumatranaNaja Naja siamensis Afronaja Naja Afronaja pallidaNaja Afronaja nubiaeNaja Afronaja katiensisNaja Afronaja nigricollisNaja Afronaja asheiNaja Afronaja mossambicaNaja Afronaja nigricincta Boulengerina Naja Boulengerina multifasciataNaja Boulengerina christyiNaja Boulengerina annulataNaja Boulengerina savannulaNaja Boulengerina subfulvaNaja Boulengerina guineensisNaja Boulengerina peroescobariNaja Boulengerina melanoleuca Uraeus Naja Uraeus niveaNaja Uraeus senegalensisNaja Uraeus hajeNaja Uraeus arabicaNaja Uraeus annuliferaNaja Uraeus anchietaeDescription edit nbsp A Caspian cobraNaja oxiana is medium in length a heavy bodied snake with long cervical ribs capable of expansion to form a hood Anteriorly the body is depressed dorsoventrally and posteriorly it is subcylindrical This species is similar in size to Naja naja averaging about 1 to 1 4 m 3 3 to 4 6 ft 10 11 in total length including tail and rarely reaches lengths over 1 7 m 5 6 ft 10 12 The head is elliptical depressed and slightly distinct from the neck with a short rounded snout and large nostrils The eye is medium in size with a round pupil The dorsal scales are smooth and strongly oblique with the outer two or three scale rows larger than the remainder 13 The hood of N oxiana has an elongated gradually tapering shape in contrast to the more ovoid hoods of some other Naja species Naja naja or Naja kaouthia 11 Juveniles tend to be pale with a faded appearance Juveniles have noticeable dark and light cross bands of approximately equal width around the body Adults of this species are completely light to chocolate brown or yellowish with some specimens retaining traces of juvenile banding especially the first few dark ventral bands This species has no hood marks and no lateral throat spots 12 Confusions may exist with the Indian cobra Naja naja as specimens without a hood mark are usually confused with this species and these two species coexist in Pakistan and northern India They re also both the only true non spitting cobras in Asia 14 The Caspian cobra Naja oxiana is never fully black although some specimens may be quite dark The Caspian cobra N oxiana normally has several dark bands under the throat whereas in the black phase of the Indian cobra N naja from Pakistan almost the entire throat is black 15 The hood has an elongate gradually tapering shape in contrast to the more ovoid hoods of some other Naja species Naja naja or Naja kaouthia 11 Scalation edit See also Snake scale Nomenclature of scales The number and pattern of scales on a snake s body are a key element of identification to species level 16 Naja oxiana has 23 to 27 usually 25 dorsal scale rows at the hood 19 23 usually 21 just ahead of midbody 191 210 ventrals and 57 71 paired subcaudals cuneate scales small angular scales between the labials are often absent 12 Distribution and habitat editNaja oxiana occurs in the Transcaspian region It is found throughout Turkmenistan Uzbekistan Kyrgyzstan southwestern Tajikistan the Fergana Valley north and east Afghanistan northeastern Iran In Iran it occurs from East Azerbaijan Province southern half of Ardabil Province to the Provinces of Zanjan and Tehran all the way to the eastern half of both Isfahan and Yazd Provinces as well the northeastern parts of Kerman Province northern part of Sistan and Baluchistan Province throughout the Provinces of Semnan Mazandaran and Golestan the entire former Province of Khorasan which was split into three separate provinces post 2004 Although this species is found throughout much of Pakistan from Balochistan and Sindh to Gilgit Baltistan and Azad Kashmir 13 it is far more common in the northern half of Pakistan This species has also been observed in far northwest India in Jammu and Kashmir union territory and also been observed in the state of Himachal Pradesh It s also highly suspected to have occurred in Ladakh 12 and in the Indian state of Punjab 13 12 There is also anecdotal evidence of it ranging as far north as Kazakhstan s southern border with Uzbekistan according to Brian Hayes a biochemical engineer with the United States Threat Reduction Agency Hayes led an expedition to Vozrozhdeniye Island in the Aral Sea in the summer of 2002 to bury anthrax on the island which is located in the Aral Sea and is split between Uzbekistan and Kazakhstan with the northern half of the island belonging to Kazakhstan Mr Hayes mentioned a 2 4 m 7 9 ft long cobra that was observed and shot near the tents where the staff lived In all we had run ins with about 25 poisonous snakes 17 The only cobra species which occurs in this region is Naja oxiana so any cobra observed in Kazakhstan would likely be of this species citation needed Naja oxiana is often found in arid and semiarid rocky or stony shrub or scrub covered foothills 13 at elevations up to about 3 000 m 9 800 ft above sea level This is also the westernmost species of Asiatic cobra 18 Ecology editBehavior edit Naja oxiana tends to avoid humans as much as it can but it can become fiercely defensive when threatened or cornered and even juveniles tend to be very aggressive When cornered and provoked it is liable to spread its hood hiss sway from side to side and strike repeatedly however it can not spit venom This terrestrial species is mainly diurnal but it may be crepuscular and nocturnal in some parts of its range during the hottest month July Caspian cobras are good climbers and able swimmers The Caspian cobra is often found in water and seldom found too far away from it 13 11 Quick moving and agile this species lives in holes in embankments or trees 18 Diet edit The Caspian Cobra feeds mostly on small mammals amphibians occasionally fish birds and their eggs It also reportedly feeds on other snakes 19 13 11 Venom editComposition edit The Caspian cobra is considered to be the most venomous species of cobra in the world Several different toxinological studies suggest this including one particular study reported in the Indian Journal of Experimental Biology in 1992 20 A study analyzing the toxic fractions of Naja oxiana venom from Iran indicated that toxic fractions constituted 78 by weight of crude venom of this species 21 similar to Naja naja 22 The toxic fractions were composed of three protein families among which the 3FTs was dominant similar to all other Naja species The venom of N oxiana was rich in short neurotoxins which make up the majority of crude venom 21 A number of small nonenzymatic proteins are found in the venom including neurotoxins and members of the cytotoxin family 23 which have been shown to cause cell death through damage to lysosomes 24 In addition to nonenzymatic proteins the venom also contains nucleases which cause tissue damage at the site of the bite and may also potentiate systemic toxicity by releasing free purines in situ 25 A ribonuclease isolated and purified from Caspian cobra venom ribonuclease V1 is commonly used as a laboratory reagent in molecular biology experiments due to its unusual ability to break down structured RNA 26 N oxiana is one of the most dangerous snakes belonging to the elapidae family Two main toxins as well as a number of minor components and three basic polypeptides similar to cardiotoxins CTXs and cytotoxins were isolated from the crude venom of this species with acute effects on cardiac system during the first few hours post envenomation There are a few case reports of acute myocardial infarction MI following bites from elapids At least one case of myocardial infarction following a bite from a Caspian cobra is recorded 27 Toxic effects edit Naja oxiana is regarded as the most dangerous snake in Central Asia and is one of the venomous snakes with a high mortality rate 28 It is one of the most dangerous elapid species in the world 27 A bite from this species will cause severe pain and swelling at the site of the bite along with the rapid onset of prominent neurotoxicity Weakness drowsiness ataxia hypotension and paralysis of the throat and limbs may appear in less than one hour after the bite In a study the first signs and symptoms of envenomation appeared within 15 minutes post envenomation Without medical treatment symptoms rapidly worsen and death can occur soon after a bite due to respiratory failure 18 As with all species of cobra there is great variation in venom toxicity and composition based on diet and geographical location Venom toxicity is highest least lethal among specimens in the eastern parts of their geographical range Indian and Pakistani specimens with a value of around 0 2 mg kg Specimens from Iran Uzbekistan northeastern Afghanistan and Turkmenistan can have considerably more potent venoms The onset of symptoms is rapid and are extremely painful Without treatment death is likely and depending on the nature of the bite the potency of the venom and the amount death can occur in as little as 45 minutes or may be prolonged for up to 24 hours 27 According to a 2019 study by Kazemi Lomedasht et al the murine LD50 via subcutaneous injection value for Naja oxiana Iranian specimens was estimated to be 0 14 mg kg 0 067 0 21 mg kg 28 more potent than the sympatric Pakistani Naja naja karachiensis 0 22 mg kg the Thai Naja kaouthia 0 2 mg kg and Naja philippinensis at 0 18 mg kg 0 11 0 3 mg kg 29 An older study by Zug et al listed a LD50 value of 0 2 mg kg from Pakistani and Indian specimens 30 Average venom yield per bite for this species is between 75 and 125 mg dry weight 13 while in other parts of its distribution venom yield average is between 150 and 225 mg dry weight 28 The highest single bite yields are between 590 31 and 784 mg dry weight 28 The crude venom of N oxiana has a lowest published lethal dose LCLo of 0 005 mg kg the lowest among all cobra species derived from an individual case of poisoning by intracerebroventricular injection 32 Between 1979 and 1987 136 confirmed bites were attributed to this species in the former Soviet Union Of the 136 121 received antivenom and only 8 died 6 6 Of the 15 who did not receive antivenom 11 died an untreated mortality rate of 73 33 34 In Iran where the Caspian cobra is widespread it is responsible for the highest number of deaths due to snakebite in the country The Levant viper Saw scaled viper and the Persian horned viper are responsible for more snakebite incidents but they have a lower mortality rate compared to N oxiana Multiplying habitat suitability models of the four snakes showed that the northeast of Iran west of Khorasan e Razavi province has the highest snakebite risk in the country In addition villages that were at risk of envenoming from the four snakes were identified Results revealed that 51 112 villages are at risk of envenoming from M lebetinus Levant viper 30 339 from E carinatus saw scaled viper 51 657 from P persicus Persian horned viper and 12 124 from N oxiana Caspian cobra A study reported 53 787 cases of bites by venomous snakes between 2002 and 2011 in Iran with the highest rate of snakebite incidents being found in provinces in the south and southwest of Iran 35 Out of the 53 787 cases of snake bites which were reported to medical centers in Iran only 118 were correctly identified as bites by this species In total there were 67 deaths 51 of which were due to N oxiana Out of the 51 bites 46 didn t receive medical treatment One 10 year old male died en route to the closest hospital 35 minutes post envenomation Five were treated with antivenom but succumbed to the venom regardless of the fact 7 mortality despite treatment Untreated mortality rates seem to be particularly high for a species within the genus Naja at around 80 35 36 5 In Pakistan it is responsible for high rates of snakebites that result in mortality 18 Reliable figures on incidence morbidity and mortality are limited but almost 40 000 biting cases are reported annually which result in up to 8 200 fatalities in one study An estimate of annual mortality rate in Pakistan is around 1 9 per 100 000 population In one survey it was reported that out of 5 337 envenomed patients 57 were cobra victims and the remaining rest of 35 were bitten by kraits and vipers Of the 5 337 envenomed patients there were 3 064 cobra N naja and N oxiana victims Out of the 3 064 bitten by cobras 841 correctly identified as N naja and 384 were correctly identified as N oxiana There were 78 untreated cases of which 64 were fatal 82 much higher than untreated cases for N naja 33 6 31 37 A woman bitten by this species in northwestern Pakistan suffered prominent neurotoxicity and died while en route to the closest hospital nearly 50 minutes after envenomation death occurred 45 50 minutes post envenomation 36 Antivenom is not as effective for envenomation by this species as it is for other Asiatic cobras within the same region like the Indian cobra N naja and due to the dangerous toxicity of this species venom massive amounts of antivenom are often required for patients As a result a monovalent antivenom serum is being developed by the Razi Vaccine and Serum Research Institute in Iran Response to treatment with antivenom is generally poor among patients so mechanical ventilation and endotracheal intubation is required As a result mortality among those treated for N oxiana envenomation is still relatively high up to 30 compared to all other species of cobra lt 1 31 References edit Ananjeva N B Orlov N L Nilson G Papenfuss T Borkin L Milto K Golynsky E Rustamov A Nuridjanov D Munkhbayar K Murthy B H C amp Mohapatra P 2021 Naja oxiana IUCN Red List of Threatened Species 2021 e T164642A1063259 doi 10 2305 IUCN UK 2021 3 RLTS T164642A1063259 en Retrieved 19 November 2021 a href Template Cite journal html title Template Cite journal cite journal a CS1 maint multiple names authors list link Appendices CITES cites org Retrieved 2022 01 14 Naja oxiana Eichwald 1831 ITIS Standard Report Page ITIS gov Retrieved 13 January 2012 Naja oxiana Eichwald 1831 Global Biodiversity Information Facility Retrieved 16 May 2023 a b Latifi Mahmoud 1991 Snakes of Iran Oxford Ohio Society for the Study of Amphibians and Reptiles ISBN 978 0 916984 22 9 Naja naja oxiana Ladle Snake p 124 Eichwald Karl 1931 Zoologia specialis quam expositis animalibus tum vivis tum fossilibus potissimuni rossiae in universum et poloniae in specie in usum lectionum publicarum in Universitate Caesarea Vilnensi in Latin Vol 3 Vilnius Zawadski p 171 Lewis CT Oxos Clarendon Press Retrieved 13 December 2021 Wuster Wolfgang 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 ISSN 0041 0101 PMID 8735239 Kazemi Elmira Nazarizadeh Masoud Fatemizadeh Faezeh Khani Ali Kaboli Mohammad 2021 The phylogeny phylogeography and diversification history of the westernmost Asian cobra Serpentes Elapidae Naja oxiana in the Trans Caspian region Ecology and Evolution 11 5 2024 2039 doi 10 1002 ece3 7144 ISSN 2045 7758 PMC 7920780 PMID 33717439 a b United States Navy Department Bureau of Medicine and Surgery January 1965 Poisonous Snakes of the World A Manual for Use by the U S Amphibious Forces 2 ed Minnesota U S Government Printing Office pp 123 124 Retrieved 26 January 2022 a b c d e Nasoori A Shahbazzadeh D Tsubota T Young BA 2016 The defensive behaviour of Naja oxiana with comments on the visual displays of cobras The Herpetological Bulletin 138 13 17 Retrieved 26 January 2022 a b c d e Species of Asiatic Naja The Asiatic Cobra Systematics Page Bangor University Retrieved 13 January 2012 a b c d e f g Naja oxiana General Details Taxonomy and Biology Venom Clinical Effects Treatment First Aid Antivenoms WCH Clinical Toxinology Resource University of Adelaide Retrieved 13 January 2012 Wuster W Thorpe RS December 1992 Dentitional Phenomena in Cobras Revisited Spitting and Fang Structure in the Asiatic Species of Naja Serpentes Elapidae Herpetologica 48 4 424 434 JSTOR 3892862 Retrieved 14 July 2021 Naja oxiana Venom Street Collector and Breeder of Asian Cobras Venom Street Archived from the original on 21 October 2014 Retrieved 3 February 2012 Hutchinson Mark Williams Ian 2018 Key to the Snakes of South Australia PDF South Australian Museum Government of South Australia Retrieved 8 February 2019 Pala Christopher 22 March 2003 Anthrax buried for good The Washington Times Archived from the original on 26 March 2023 via University of California Los Angeles Department of Epidemiology a b c d Naja oxiana Armed Forces Pest Management Board United States Department of Defense Archived from the original on 11 January 2012 Retrieved 14 January 2012 Bhardwaj Virender Kumar Kapoor Rakeshwar 2022 07 22 A report on ophiophagy observed in Naja oxiana Eichwald 1831 from Himachal Pradesh India Hamadryad 39 1 Khare AD Khole V Gade PR December 1992 Toxicities LD50 prediction and in vivo neutralisation of some elapid and viperid venoms Indian Journal of Experimental Biology 30 12 1158 62 PMID 1294479 a b Samianifard M Nazari A Tahoori F Mohammadpour Dounighi N 1 March 2021 Proteome Analysis of Toxic Fractions of Iranian Cobra Naja naja Oxiana Snake Venom Using Two Dimensional Electrophoresis and Mass Spectrometry Archives of Razi Institute 76 1 127 138 doi 10 22092 ari 2020 128766 1428 PMC 8410206 PMID 33818965 Dutta S Chanda A Kalita B Islam T Patra A Mukherjee AK 6 March 2017 Proteomic analysis to unravel the complex venom proteome of eastern India Naja naja Correlation of venom composition with its biochemical and pharmacological properties Journal of Proteomics 156 29 39 doi 10 1016 j jprot 2016 12 018 PMID 28062377 Retrieved 28 December 2021 Dementieva Daria V Bocharov Eduard V Arseniev Alexander S 1999 Two forms of cytotoxin II cardiotoxin from Naja naja oxiana in aqueous solution Spatial structures with tightly bound water molecules European Journal of Biochemistry 263 1 152 162 doi 10 1046 j 1432 1327 1999 00478 x PMID 10429199 Sharonov George V Feofanov Alexei V Astapova Maria V Rodionov Dmitriy I Utkin Yuriy N Arseniev Alexander S 2005 Cancer cell injury by cytotoxins from cobra venom is mediated through lysosomal damage Biochemical Journal 390 1 11 18 doi 10 1042 BJ20041892 PMC 1184559 PMID 15847607 Dhananjaya BL D souza CJ 2010 An overview on nucleases DNase RNase and phosphodiesterase in snake venoms Biochemistry Moscow 75 1 1 6 doi 10 1134 S0006297910010013 PMID 20331418 S2CID 37575193 Ying Shao Yao ed 2006 MicroRNA Protocols Humana Press p 23 ISBN 9781597451239 Retrieved 28 January 2015 a b c Angaji SA Houshmandi A Zare Mirakabadi A December 2016 Acute Effects of the Iranian Snake Naja Naja Oxiana Venom on Heart PDF Biomacromolecular Journal 2 2 97 101 a b c d Kazemi Lomedasht F Yamabhai M Sabatier J Behdani M Zareinejad MR Shahbazzadeh D 5 December 2019 Development of a human scFv antibody targeting the lethal Iranian cobra Naja oxiana snake venom Toxicon 171 78 85 doi 10 1016 j toxicon 2019 10 006 PMID 31622638 S2CID 204772656 Retrieved 28 December 2021 Wong KY Tan CH Tan NH 3 January 2019 Venom and Purified Toxins of the Spectacled Cobra Naja naja from Pakistan Insights into Toxicity and Antivenom Neutralization The American Journal of Tropical Medicine and Hygiene 94 6 1392 1399 doi 10 4269 ajtmh 15 0871 PMC 4889763 PMID 27022154 Zug George R in German 1996 Snakes in Question The Smithsonian Answer Book Washington District of Columbia Smithsonian Institution Scholarly Press ISBN 978 1 56098 648 5 a b c Latifi M 1984 Variation in yield and lethality of venoms from Iranian snakes Toxicon 22 3 373 380 doi 10 1016 0041 0101 84 90081 3 PMID 6474490 Lysz Thomas W Rosenberg Philip May 1974 Convulsant activity of Naja naja oxiana venom and its phospholipase A component Toxicon 12 3 253 265 doi 10 1016 0041 0101 74 90067 1 PMID 4458108 Gopalakrishnakone P Chou LM 1990 Snakebite a medical and public health problem in Pakistan Snakes of Medical Importance Asia Pacific Region ed Singapore National University Singapore pp 447 461 ISBN 9971622173 Wuster W Thorpe RS March 1992 Asiatic Cobras Population Systematics of the Naja naja Species Complex Serpentes Elapidae in India and Central Asia Herpetologica 48 1 69 85 JSTOR 3892921 Retrieved 9 May 2021 a b Yousefi M Kafash A Khani A Nabati N 22 October 2020 Applying species distribution models in public health research by predicting snakebite risk using venomous snakes habitat suitability as an indicating factor Sci Rep 10 18073 18073 Bibcode 2020NatSR 1018073Y doi 10 1038 s41598 020 74682 w PMC 7582189 PMID 33093515 a b Gopalakrishnakone P Chou L M eds 1990 Snakes of Medical Importance Asia Pacific Region Singapore National University of Singapore ISBN 978 9971 62 217 6 page needed Kasturiratne A Wickremasinghe AR de Silva N Gunawardena NK Pathmeswaran A November 2008 The global burden of snakebite a literature analysis and modelling based on regional estimates of envenoming and deaths PLOS Medicine 5 11 e218 doi 10 1371 journal pmed 0050218 PMC 2577696 PMID 18986210 Further reading editWuster Wolfgang 1993 A century of confusion Asiatic cobras revisited Vivarium 4 4 14 18 Wuster Wolfgang Thorpe Roger S 1991 Asiatic cobras Systematics and snakebite Experientia 47 2 205 209 doi 10 1007 BF01945429 PMID 2001726 S2CID 26579314 Wuster W Thorpe RS 1992 Asiatic Cobras Population Systematics of the Naja naja Species Complex Serpentes Elapidae in India and Central Asia Herpetologica 48 1 69 85 JSTOR 3892921 Wuster W 1998 The cobras of the genus Naja in India Hamadryad 23 1 15 32 External links editNaja oxiana at the Reptarium cz Reptile Database Retrieved from https en wikipedia org w index php title Caspian cobra amp oldid 1172976365, wikipedia, wiki, book, books, library,

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