Ophiophagus Research Articles

First photographic evidence of the King Cobra, Ophiophagus Hannah (Cantor 1836), from Bardia National Park, Nepal

First photographic evidence of the King Cobra, Ophiophagus Hannah (Cantor 1836), from Bardia National Park, Nepal

Discovery and optimization of a broadly-neutralizing human monoclonal antibody against long-chain α-neurotoxins from snakes

Snakebite envenoming continues to claim many lives across the globe, necessitating the development of improved therapies. To this end, broadly-neutralizing human monoclonal antibodies may possess advantages over current plasma-derived antivenoms by offering superior safety and high neutralization capacity. Here, we report the establishment of a pipeline based on phage display technology for the discovery and optimization of high affinity broadly-neutralizing human monoclonal antibodies. This approach yielded a recombinant human antibody with superior broadly-neutralizing capacities in vitro and in vivo against different long-chain α-neurotoxins from elapid snakes. This antibody prevents lethality induced by Naja kaouthia whole venom at an unprecedented low molar ratio of one antibody per toxin and prolongs the survival of mice injected with Dendroaspis polylepis or Ophiophagus hannah whole venoms.

Prehistoric snake bones from Zuojiang River Basin, Guangxi, China

ABSTRACT Based on the morphological studies on the snake bones discovered in the Neolithic sites from the Zuojiang River Basin, Chongzuo, Guangxi, China, three extant snake species attributed to three different genera and three families have been identified: Elaphe moellendorffi (Boettger, 1886), Ophiophagus hannah (Cantor, 1836), and Python bivittatus Kuhl, 1820. Multiple linear regression of four vertebral measurements against the body size for extant specimens using an allometric model indicates a minimum snout-vent length of 3 882.5 mm, total body length of 4 578.7 mm for the largest vertebra of the Neolithic P. bivittatus found in this region. The result indicates a similar herpetofauna between the Neolithic period and current southwest Guangxi, in addition to a potential snake hunting lifestyles of pre-historical humans from the Zuojiang River basin.

House-warming: Wild king cobra nests have thermal regimes that positively affect hatching success and hatchling size

Incubation temperature in nests of oviparous reptiles affects reproductive success indicators, including hatching time and success, offspring size, fitness, and behaviour. The female king cobra builds an above ground nest to incubate and protect its eggs. However, it is not clear how thermal regimes inside king cobra nests respond to external environmental temperature regimes, especially in subtropical regions that witness high diel and seasonal temperature fluctuations. To better understand the relationship between inside nest temperatures and hatching outcomes for this snake, we monitored the thermal regimes of 25 natural king cobra nests in the subtropical forests of the Western Himalayas in Uttarakhand state, northern India. We hypothesized that inside nest temperatures would be higher than outside (ambient) temperatures and that thermal regimes inside nests would affect hatching success and hatchling size. Internal and external temperatures at nest sites were measured every hour until hatching, via automatic data loggers. We then calculated hatching success of eggs and measured hatchling length and weight. Mean inside nest temperatures were consistently higher by about 3.0 °C than outside environmental temperatures. External temperature reduced with increasing elevation of nest sites and was the best determinant of inside nest temperature, which had a smaller range of variability. Physical characteristics of nests (size and leaf materials used) did not influence nest temperature significantly, but nest size was positively related to clutch size. Mean inside nest temperature was the best predictor of hatching success. Average daily minimum nest temperature, which indicates a possible lower threshold for thermal tolerance by eggs, was also correlated positively with hatching success. Mean daily maximum temperature was a significant predictor of mean length of hatchlings, but not of mean hatchling weight. Our study provides unequivocal evidence for the critical thermal benefits of king cobra nests for increased reproductive success, in subtropical environments with lower and sharply fluctuating temperature regimes.

King Cobras, Ophiophagus hannah (Cantor 1836), from Lumding, Hojai District, Assam, India

King Cobras, Ophiophagus hannah (Cantor 1836), from Lumding, Hojai District, Assam, India

Preclinical assessment of VPEAV, a new trivalent antivenom for elapid snakebite envenoming in the Philippines: Proteomics, immunoreactivity and toxicity neutralization

Snakebite envenoming is an important neglected tropical disease. Antivenom supply, however, remains limited in many parts of the world. This study aimed to examine the protein composition, immunoreactivity and neutralization efficacy of a new antivenom product (VINS Philippine Elapid Antivenoms, VPEAV) developed for the treatment of snakebite envenoming caused by the Philippine Cobra (Naja philippinensis), Samar Cobra (Naja samarensis) and King Cobra (Ophiophagus hannah). Size-exclusion chromatography, sodium-dodecyl sulfate-polyacrylamide gel electrophoresis and tandem mass spectrometry showed that VPEAV consisted of F(ab)’2 (∼90% of total antivenom proteins) with minimal protein impurities. Indirect ELISA showed varying immunoreactivity of VPEAV toward the different venoms (EC50 = 4–16 μg/ml), indicating distinct venom antigenicity between the species. In mice, the neutralization potency of VPEAV against the King Cobra venom was moderate (potency, P = 2.6 mg/ml, defined as the amount of venom completely neutralized per unit volume of antivenom). The potency was significantly lower against the N. philippinensis and N. samarensis venoms (P = 0.18–0.30 mg/ml), implying a higher dose may be needed for effective neutralization of the Naja venoms. Together, the findings suggest the potential and limitation of VPEAV in neutralizing the venom toxicity of the three Philippine elapid snakes.

In Vitro neurotoxicity and myotoxicity of Malaysian Naja sumatrana and Naja kaouthia venoms: Neutralization by monovalent and Neuro Polyvalent Antivenoms from Thailand.

Naja sumatrana and Naja kaouthia are medically important elapids species found in Southeast Asia. Snake bite envenoming caused by these species may lead to morbidity or mortality if not treated with the appropriate antivenom. In this study, the in vitro neurotoxic and myotoxic effects N. sumatrana and N. kaouthia venoms from Malaysian specimens were assessed and compared. In addition, the neutralizing capability of Cobra Antivenom (CAV), King Cobra Antivenom (KCAV) and Neuro Polyvalent Antivenom (NPAV) from Thailand were compared. Both venoms produced concentration-dependent neurotoxic and myotoxic effects in the chick biventer cervicis nerve-muscle preparation. Based on the time to cause 90% inhibition of twitches (i.e. t90) N. kaouthia venom displayed more potent neurotoxic and myotoxic effects than N. sumatrana venom. All three of the antivenoms significantly attenuated venom-induced twitch reduction of indirectly stimulated tissues when added prior to venom. When added after N. sumatrana venom, at the t90 time point, CAV and NPAV partially restored the twitch height but has no significant effect on the reduction in twitch height caused by N. kaouthia venom. The addition of KCAV, at the t90 time point, did not reverse the attenuation of indirectly stimulated twitches caused by either venom. In addition, none of the antivenoms, when added prior to venom, prevented attenuation of directly stimulated twitches. Differences in the capability of antivenoms, especially NPAV and CAV, to reverse neurotoxicity and myotoxicity indicate that there is a need to isolate and characterize neurotoxins and myotoxins from Malaysian N. kaouthia and N. sumatrana venoms to improve neutralization capability of the antivenoms.

Favourable climatic niche in low elevations outside the flood zone characterises the distribution pattern of venomous snakes in Bangladesh

AbstractSnakes are sensitive to both environmental and climate gradients. To design conservation plans, a scientific understanding of snake habitats in light of environmental and climatic variables is an essential prerequisite. For venomous snakes, denoting favourable habitats should also be relevant for snakebite management. We have considered 18 spatial variables to portray the range of terrestrial venomous snake distribution in Bangladesh. Our results indicate that the distribution of 29 studied venomous snakes in this country is primarily driven by climatic and environmental variables. We found that especially low elevation and flood risk constrain the distribution of those terrestrial snakes, i.e. regular floods in central Bangladesh push venomous snakes towards the edges of the country. Moreover, none of these species occupies the whole of its anticipated climatically favourable area. Projections into the future indicated that 11 studied species, Amphiesma platyceps, Boiga siamensis, Chrysopelea ornata, Pseudoxenodon macrops, Rhabdophis himalayanus, Rhabdophis subminiatus, Bungarus lividus, Ophiophagus hannah, Daboia russelii, Ovophis monticola and Trimeresurus popeiorum will lose their entire climatically suitable area within the country. Therefore, we suggest establishing more protected areas in the hilly ecosystems in the eastern part and in the mangrove forests in the south-western corner of Bangladesh to mitigate future extinction risks, such as climate change, sea-level rise and increase in flood severity. Conserving village forests and croplands, which are subject to rapid change, will also need to be addressed equally, as these are inhabited by almost one-third of the studied species. The occurrence of the cobras and kraits in village forests and cropland dominant habitats demands more attention to minimise snakebite related mortality and morbidity.

The Target Selects the Toxin: Specific Amino Acids in Snake-Prey Nicotinic Acetylcholine Receptors That Are Selectively Bound by King Cobra Venoms.

Snake venom is an adaptive ecological trait that has evolved primarily as a form of prey subjugation. Thus, the selection pressure for toxin diversification is exerted by the prey’s physiological targets, with this pressure being particularly acute for specialist feeders, such as the King Cobra species, all of which are snake-prey specialists. However, while extensive research has been undertaken to elucidate key amino acids that guide toxin structure–activity relationships, reciprocal investigations into the specific sites guiding prey-lineage selective effects have been lacking. This has largely been due to the lack of assay systems amenable to systematic amino acid replacements of targeted proteins in the prey’s physiological pathways. To fill this knowledge gap, we used a recently described approach based upon mimotope peptides corresponding to the orthosteric site of nicotinic acetylcholine receptor alpha-1 subunits, a major binding site for snake venom neurotoxins that cause flaccid paralysis. We investigated the venoms of four different types of King Cobra (Cambodian, Javan, Malaysian, and Thai). This approach allowed for the determination of the key amino acid positions in King Cobra snake prey that are selectively bound by the toxins, whereby replacing these amino acids in the snake-prey orthosteric site with those from lizards or rats resulted in a significantly lower level of binding by the venoms, while conversely replacing the lizard or rat amino acids with those from the snake at that position increased the binding. By doing such, we identified three negatively charged amino acids in the snake orthosteric site that are strongly bound by the positively charged neurotoxic three-finger toxins found in King Cobra venom. This study, thus, sheds light on the selection pressures exerted by a specialist prey item for the evolution of lineage-selective toxins.

An immunodetection assay developed using cobra cytotoxin-specific antibodies: Potential diagnostics for cobra envenoming

Cobra (Naja spp.) envenoming is a life-threatening medical emergency, and a correct diagnosis is crucial to initiating timely and appropriate antivenom treatment. However, snakebite diagnostics remain unavailable in Southeast Asia. This study, therefore, developed an immunodetection assay with a potential diagnostic application for cobra envenoming. The cytotoxin of Naja kaouthia (Thai Monocled Cobra) (Nk-CTX) was purified from its venom to produce CTX-specific antibodies in rabbits and chickens. A double-antibody sandwich enzyme-linked immunosorbent assay was developed using the purified anti-Nk-CTX antibodies (immunoglobulin G and immunoglobulin Y), and its selectivity, specificity, and sensitivity for the venoms of five major cobra species in Southeast Asia (N. kaouthia, Naja sumatrana, Naja sputatrix, Naja siamensis, and Naja philippinensis) were studied. The results showed the immunoassay discriminates cobra venoms from other species commonly implicated in snakebites in Southeast Asia, i.e., the Malayan Krait, Many-banded Krait, King Cobra, Eastern Russell's Viper, Malayan Pit Viper and White-lipped Pit Viper. The immunoassay has a high sensitivity for the five cobra venoms, with detection limits (LoD) ranging from 0.6 to 2.6 ng/ml. Together, the findings suggest the potential diagnostic application of the cytotoxin immunoassay for cobra envenoming. The immunoassay was found to exhibit high immunoreactivity toward ten Asiatic cobra venoms (absorbance > 1.5), in contrast to African cobra venoms with low immunoreactivity (absorbance < 0.9). Considering the varying CTX antigenicity between Asiatic and African cobras, the immunoassay for African cobras should utilize antibodies produced specifically from the cytotoxins of African cobra venoms.

Present Status, Challenges and Prospects of Snake Farming in Bangladesh

Venomous snakes are one of the most dreadful animals globally that kill their victims by injecting venoms (toxic substances) using fangs. However, snakes are being used for numerous vital life-saving purposes, including antivenom and traditional medicines, pain killers, cancer treatment, cardiac arrest, paralysis, arthritis, anti-ageing, and cosmetics to leather products, foods, display and research. This study was conducted to investigate the current status, challenges and prospects of snake farming in Bangladesh using self-structured questionnaires surveys. In this study, in total, 281 snakes belonging to 12 species i.e., common krait Bungarus caeruleus, banded krait B. fasciatus, greater black krait Bungarus niger, monocled cobra Naja kaouthia, spectacled cobra Naja naja, king cobra Ophiophagus hannah, russell's viper Daboia russelii, indian python Python molurus, common sand boa Eryx conicus, common cat snake Boiga trigonata, common wolf snake Lycodon aulicus and rat snake Ptyas mucosa were observed. This study also showed that the largest snake farm was at Patuakhali, where about 231 venomous snake individuals were reared, while 35 snakes were reared in Rajshahi farm, eight and seven snakes were reared in Rajbari and Gazipur farms, respectively. These snakes were collected from snake catchers/charmers and rescued from several places and nature. Snakes were fed on natural feeds (toad, frog, rat, and snake) and chickens. These farms had small to medium tin-shed building infrastructure with minimal facilities and used tanks, cages, and vivaria for snake rearing, breeding, and displaying. Snake farmers had not received any training, but some skilled snake handlers operated these farms. These snake farms did not keep managemental activities records and lack of proper design. These were not collected and preserved snake venom and were mainly involved in snake displaying. Although this study did not explore much information but snake farming may have great potential in Bangladesh; thus, more research is warranted on proper snake farming facilities. However, the government could be initiated the establishment of a modern and sophisticated snake farm for research, development, conservation, and venom collection including antivenom production and pharmaceutical purposes. Hence, the existing snake resources and skilled professionals may assist the government in snake farming activities. Bangladesh J. Zool. 50 (1): 121-133, 2022

The Effect of Australian and Asian Commercial Antivenoms in Reversing the Post-Synaptic Neurotoxicity of O. hannah, N. naja and N. kaouthia Venoms In Vitro.

Despite antivenoms being the only established specific treatment for neuromuscular paralysis arising from snake envenoming, their ability to reverse the post-synaptic neurotoxicity in snake envenoming is poorly understood. We investigated the ability of five commercial antivenoms i.e., King cobra monovalent, Thai cobra monovalent, Thai neuro polyvalent, Indian polyvalent and Australian polyvalent antivenoms to reverse neurotoxicity induced by the venoms of King cobra (Ophiophagus hannah, 3 µg/mL), Indian cobra (Naja naja, 5 µg/mL) and Thai cobra (Naja kaouthia, 3 µg/mL) using the in vitro chick-biventer cervicis nerve–muscle preparation. All three venoms displayed post-synaptic neurotoxicity, which was prevented by all tested antivenoms (40 µL/mL) added to the bath prior to venom. All antivenoms partially reversed the established post-synaptic neuromuscular block after the addition of the three venoms during a 180 min observation period, but to varying degrees and at different rates. The neurotoxic effects of O. hannah venom recovered to a greater magnitude (based on twitch height restoration) and faster than the neurotoxicity of N. kaouthia venom, which recovered to a lower magnitude more slowly. The recovery of post-synaptic neurotoxicity by N. naja venom was hindered due to the likely presence of cytotoxins in the venom, which cause direct muscle damage. The observations made in this study provide further evidence that the commercial antivenoms are likely to actively reverse established α-neurotoxin-mediated neuromuscular paralysis in snake envenoming, and there is cross-neutralisation with different antivenoms.

In silico Exploration of Phospholipase A2 Inhibitor Compounds from Lufariella variabilis as Antivenom of Ophiophagus hannah

The King Cobra (Ophiophagus hannah) is a venomous snake found in Southeast Asia and South Asia. Globally, it is estimated that there are 81,000 to 138,000 cases of snakebite deaths from 1.8 million to 2 million snakebite cases. The limited availability of antivenom is a problem in handling snake venom poisoning. Exploration of natural ingredients is needed as a preventive measurement from the spread of toxins when they are inside the body. Exploration could be carried out by utilizing natural metabolite compounds that can be inhibitors of the phospholipase A2 (PLA2) enzyme. Luffariella variabilis is known as a marine organism that can produce sesterterpenoid compounds and has the potential as an inhibitor of the phospholipase A2 enzyme. This study aims to explore the potential of sesterterpenoid compounds produced by Luffariella variabilis as an in silico inhibitor of phospholipase A2. Several methods used in this research are molecular docking simulation, toxicity test using pkCSM and Toxtree, and chemical bond analysis using Discovery Studio. The results showed that the manoalide compound was the most potent compound of the other sesterterpenoid compounds in its ability to become a snake antivenom candidate.

Isolation and Pharmacological Characterization of α-Elapitoxin-Oh3a, a Long-Chain Post-Synaptic Neurotoxin From King Cobra (Ophiophagus hannah) Venom.

The King Cobra (Ophiophagus hannah) is the world’s largest venomous snake and has a widespread geographical distribution throughout Southeast Asia. Despite proteomic studies indicating the presence of postsynaptic neurotoxins in O. hannah venom, there are few pharmacological investigations of these toxins. We isolated and characterized α-elapitoxin-Oh3a (α-EPTX-Oh3a; 7,938 Da), a long-chain postsynaptic neurotoxin, which constitutes 5% of O. hannah venom. α-EPTX-Oh3a (100–300 nM) caused concentration-dependent inhibition of indirect twitches and inhibited contractile responses of tissues to exogenous acetylcholine and carbachol, in the chick biventer cervicis nerve-muscle preparation. The prior incubation of tissues with Thai Red Cross Society King Cobra antivenom (1 ml/0.8 mg) prevented the in vitro neurotoxic effects of α-EPTX-Oh3a (100 nM). The addition of Thai Red Cross Society King Cobra antivenom (1 ml/0.8 mg), at the t90 time point partially reversed the in vitro neurotoxicity of α-EPTX-Oh3a (100 nM). Repeatedly washing the tissue did not allow significant recovery from the in vitro neurotoxic effects of α-EPTX-Oh3a (100 nM). α-EPTX-Oh3a demonstrated pseudo-irreversible antagonism of concentration-response curves to carbachol, with a pA2 of 8.99. De novo sequencing of α-EPTX-Oh3a showed a long-chain postsynaptic neurotoxin with 72 amino acids, sharing 100% sequence identity with Long neurotoxin OH-55. In conclusion, the antivenom is useful for reversing the clinically important long-chain α-neurotoxin-mediated neuromuscular paralysis.

How do King Cobras move across a major highway? Unintentional wildlife crossing structures may facilitate movement.

Global road networks continue to expand, and the wildlife responses to these landscape‐level changes need to be understood to advise long‐term management decisions. Roads have high mortality risk to snakes because snakes typically move slowly and can be intentionally targeted by drivers.We investigated how radio‐tracked King Cobras (Ophiophagus hannah) traverse a major highway in northeast Thailand, and if reproductive cycles were associated with road hazards.We surveyed a 15.3 km stretch of Highway 304 to determine if there were any locations where snakes could safely move across the road (e.g., culverts and bridges). We used recurse analyses to detect possible road‐crossing events, and used dynamic Brownian Bridge Movement Models (dBBMMs) to show movement pathways association with possible unintentional crossing structures. We further used Integrated Step Selection Functions (ISSF) to assess seasonal differences in avoidance of major roads for adult King Cobras in relation to reproductive state.We discovered 32 unintentional wildlife crossing locations capable of facilitating King Cobra movement across the highway. While our dBBMMs broadly revealed underpasses as possible crossing points, they failed to identify specific underpasses used by telemetered individuals; however, the tracking locations pre‐ and post‐crossing and photographs provided strong evidence of underpass use. Our ISSF suggested a lower avoidance of roads during the breeding season, although the results were inconclusive. With the high volume of traffic, large size of King Cobras, and a 98.8% success rate of crossing the road in our study (nine individuals: 84 crossing attempts with one fatality), we strongly suspect that individuals are using the unintentional crossing structures to safely traverse the road.Further research is needed to determine the extent of wildlife underpass use at our study site. We propose that more consistent integration of drainage culverts and bridges could help mitigate the impacts of roads on some terrestrial wildlife.

04. Collection of vulnerable nests with eggs for the captive incubation of king cobra [Ophiophagus hannah] as a conservation strategy in Mizoram north-east India

04. Collection of vulnerable nests with eggs for the captive incubation of king cobra [Ophiophagus hannah] as a conservation strategy in Mizoram north-east India

Collection of vulnerable nests with eggs for the captive incubation of king cobra Ophiophagus hannah as a conservation strategy in Mizoram north-east India

Collection of vulnerable nests with eggs for the captive incubation of king cobra Ophiophagus hannah as a conservation strategy in Mizoram north-east India

Epidemiological analysis of 952 venomous snake bite in Wuzhou City of Guangxi Zhuang Autonomous Region

To improve the prevention and treatment of venomous snake bites by analyzing the epidemiological characteristics of venomous snake bite in Wuzhou City, Guangxi Zhuang Autonomous Region. A retrospective analysis was conducted. The medical records of 1 091 patients with venomous snake bites admitted to the department of snake wound of Wuzhou Hospital of Traditional Chinese Medicine from January 2014 to December 2020 were collected, including snake species, gender and age of patients, bite time, bite site and local symptom. The medical records of 952 patients with a definite clinical diagnosis of snake bite were enrolled. Among the 952 patients with venomous snake bites, the main bites were from Ovophis (32.98%), Trimeresurus (27.84%) and Naja (26.26%), followed by Bungarus multicinctus (6.51%), Ophiophagus Hannah (3.15%) and Agkistrodonhalys (1.58%), and few bites were from Rhabdophis subminiatus (0.73%), Bungarus fasciatus (0.42%), viper (0.32%) and Agkistrodon (0.21%). Of the 952 patients with venomous snake bites, there were almost twice as many males as females [647 cases (67.96%) vs. 305 cases (32.04%), with male to female ratio of 2.12:1]. The age of patients ranged from 0.8 to 87.0 years old, with 40-59 years old as the majority (42.44%), followed by ≥ 60 years old (27.31%). Snake bites mainly occurred from April to November (93.59%), with a peak in October (16.39%). The incidence time was mainly afternoon (12:00-17:59, 30.88%) and evening (18:00-23:59, 33.30%), followed by morning (06:00-11:59, 24.69%), and early in the morning (00:00-05:59, 11.13%). The incidence time of Ovophis and Bungarus multicinctus mainly concentrated in 18:00-23:59, the time of Trimeresurus was in 06:00-11:59, and that of Naja and Ophiophagus hannah was in 12:00-17:59. Most cases of snake bite were on limbs (98.53%), and mainly on the right limbs (53.57%). The lower limbs mainly were bitten by Ovophis, while the upper limbs mainly were bitten by Naja and by Ophiophagus hannah. The local symptoms of the bite of Ovophis and Trimeresurus were similar, mainly including pain, swelling, tenderness, high temperature of skin around the wound, bleeding and exudation, etc. And the local symptoms of the bite of Naja were pain, swelling, bruising, tenderness, bleeding and exudation, red skin, etc. Numbness and mild pain were the main symptoms of the bite of Bungarus multicinctus and Bungarus fasciatus, but other local characteristics were not obvious. The majority of venomous snake bite patients in Wuzhou City of Guangxi were middle-aged and elderly males, and the majority of venomous snakes were Ovophis, Trimeresurus, and Naja. Most venomous snake bite occurs from April to November, and the incidence time was concentrated between 12:00 and 23:59. The majority of venomous snake bite was limb bites. The local symptoms were pain, swelling, tenderness, high temperature of skin around the wound, bruising, etc. To reduce the incidence rate, disability rate and mortality of snake bite disease, a snake bite prevention system should be established, the education and publicity of snake bite prevention knowledge should be strengthened, the awareness of snake bite prevention should be improved, and clinical diagnosis and treatment should be assisted, based on the epidemiological characteristics of snake bite in Wuzhou area.

Biogeographic Inferences on the Evolutionary History of the King Cobra (Ophiophagus hannah, Cantor 1836) Species Complex.

King cobra (Ophiophagus hannah) is a snake widely distributed through southeastern tropical Asia, but in two separate subpopulations: one located in the Western Ghats (western Indian Peninsula) and the other much more extensive, ranging between the southern slopes of the Himalayas, Assam, Indochina to southeastern China. Similarly, it also appears in numerous tropical archipelagos such as Indonesia, the Philippines, and the Andaman Islands, but surprisingly it is absent from other large islands like Sri Lanka and Taiwan. In this study, we evaluated how climate could be shaping the distribution of this snake and estimated the future distribution of the species utilizing ecological niche modelling. To evaluate the effect of paleoclimatic conditions on the genetic structure of this species we performed Bayesian phylogenetic analysis under a molecular clock using mitochondrial DNA. Our analyses indicated that the current distribution of O. hannah is strongly influenced by the availability of humid climate conditions. King cobras have a long evolutionary history reflected in the appearance of four main mitochondrial lineages before the Pliocene (the Western Ghats, southeastern mainland Asia, Luzon, and Indonesia), congruently with paleoclimatic models that indicated the availability of suitable conditions for this species in these refugia during the glacial cycles. Climate history could explain the absence of O. hannah in Sri Lanka and Taiwan due to the absence of suitable climatic corridors when these islands were connected to the mainland (20,000 years ago). Future projections (2050‒2070) did not suggest significant range shifts in the region, even considering the worst global warming scenarios.

Insilico structural and functional assessment of hypothetical protein L345_13461 from Ophiophagus hannah

Insilico structural and functional assessment of hypothetical protein L345_13461 from Ophiophagus hannah