THE BIS-COBRA – INDIA'S VENOMOUS LIZARD THAT NEVER WAS

First edition of EHA's delightful book, The Tribes On My Frontier (public domain)

Snakes of all kinds are held in great horror by the natives of India, and they slay indiscriminately and ruthlessly all they come across, but this horror pales before the terror inspired even by the names of the bis-cobra and goh-sámp,—terror so great, that, if met with, the harmless animals are given the widest berth possible, and their destruction is never attempted. Though actual animals, they are virtually mythical, that is as regards the deadly properties assigned to them, and we easily recognise in them the originals of the flame-breathing dragon and deadly basilisk. The gaze of the bis-cobra is awful even from a distance and its bite is instant death; and if the goh-sámp breathes upon, or at you, you fall dead at once.

   H.F. Hutchinson – Nature, 9 October 1879

In villages across the length and breadth of India even today, there remains tangible fear concerning a creature that may be small in size but is gargantuan in terms of the terror that the mere sight of it generates. Known most commonly as the bis-cobra, according to generations of fervently-believed native folklore and superstition this modest-sized Asian lizard has such a venomous bite that anyone so inflicted will die instantly. Needless to say, no species matching this description is known to science. Yet there is no doubt that the bis-cobra does exist. So what precisely is this noxious entity, and how can these contradictions be resolved?

The name 'bis-cobra' (or 'biscopra'), which is used most prevalently in western India, loosely translates as 'venomous cobra'. Bearing in mind that all cobras are venomous, this is a particularly direct, hard-hitting way of emphasising just how exceptionally toxic this animal is – or, to be more accurate, allegedly is.

I first read about the bis-cobra many years ago, when perusing a delightful, humorous book on Indian wildlife entitled The Tribes On My Frontier, published in 1904 and written by 'EHA' - the pen-name of Indian amateur naturalist and artist Edward Hamilton Aitken (1851-1909). His description of it summarises very succinctly the basic attributes of this mysterious reptile:

But of all the things in this earth that bite or sting, the palm belongs to the biscobra, a creature whose very name seems to indicate that it is twice as bad as the cobra. Though known by the terror of its name to natives and Europeans alike, it has never been described in the proceedings of any learned society, nor has it yet received a scientific name. In fact, it occupies much the same place in science as the sea-serpent, and accurate information regarding it is still a desideratum. The awful deadliness of its bite admits of no question, being supported by countless authentic instances; our own old ghorawalla [horse-keeper] was killed by one. The points on which evidence is required are – first, whether there is any such animal as the biscobra; second, whether, if it does exist, it is a snake with legs or a lizard without them. By inquiry among natives I have learned a few remarkable facts about it, as, for instance, that it has eight legs, and is a hybrid between a cobra and that gigantic lizard commonly miscalled an iguana [in India, 'iguana' is a term popularly misapplied to monitor lizards]; but last year a brood of them suddenly appeared in Dustypore, and I saw several. The first was killed by some of the bravest of my own men with stones, for it can spring four feet, and no one may approach it without hazard of life. Even when dead it is exceedingly dangerous, but, with my usual hardihood, I examined it. It was nine inches long, and in appearance like a pretty brownish lizard spotted with yellow. It has no trace of poison-fangs, but I was assured that an animal so deadly could dispense with these. If it simply spits at a man his fate is sealed.

After some effort, EHA finally managed to capture a bis-cobra alive in his own garden using a butterfly-net, much to the great consternation of his native butler, watching the proceedings from a considerable distance. He then kept it for a time as a pet, without suffering any adverse effects.

EHA's own bis-cobra drawing in The Tribes On My Frontier (public domain)

Pre-dating EHA's account by several decades, however, was a lengthy report on the bis-cobra by a Mr John Grant that featured in the inaugural volume of the Calcutta Journal of Natural History, published in 1840. In it, Grant referred to a specimen of a reputed bis-cobra specially captured for him to examine. Approximately 6 in long, it was attractively patterned with irregular streaks of small bead-like markings of alternating dark and light grey colour. Anxious to observe its lethal effect, Grant introduced a mouse into the glass container housing this lizard. But far from the mouse meeting a rapid demise, it fought spiritedly with the lizard for a short time, each biting the other, before the two combatants retreated to opposite sides of the container, neither of them appearing any worse for their savage encounter. So much for the bis-cobra's virulent venom.

In her book East of Suez (1901), Alice Perrin included an eventful incident in which a European living in India demonstrated dramatically but beyond any doubt that the bite of a bis-cobra was harmless. He achieved this by lifting a brown and yellow specimen out of a pot in which it had been trapped, and then, when it seized hold of his hand with its teeth, holding it up, still biting him, for all of his horror-stricken native helpers to witness. After anxiously waiting for a while to watch their doomed master's fully-anticipated demise, they finally dispersed when it became clear that he was totally unharmed. Perrin also documented an encounter with a tree-climbing bis-cobra, measuring about 14 in long.

Alice Perrin's book East of Suez, Speaking Tiger Books reprint, 2015 (© Speaking Tiger Books, reproduced here on a strictly non-commercial Fair Use basis only)

EHA was not the only source of native lore claiming that the bis-cobra doesn't even have to bite in order for its venom to prove lethal. Several other writers have also alleged that it only has to spit a single drop onto someone's skin for its potency to prove instantaneously fatal, searing through the victim's skin, entering their bloodstream, and eliciting certain death. Indeed, in his book Indian Peepshow (1937), Henry Newman was even assured by a local man that if this dire lizard so much as spat at a tree (let alone a person), a hole would burn right through and the tree would die.

In parts of India outside the western zone where reports of the bis-cobra are most rife, this supposedly deadly beast is conflated with another mysterious but equally malign reptile called the hun khun. Likened to a small slow-moving lizard with a fat tail, much the same powers of venomous potency are attributed to it as to the bis-cobra, but even the blood of the hun khun is reportedly toxic, and its skin reputedly contains lethal poison glands.

As science knows of no species corresponding to the bis-cobra, how can this enigmatic lizard be explained? Down through the decades, several different zoological identities have been proposed for it. In their book Venomous Reptiles (1969), Sherman and Madge Minton proposed that the bis-cobra was the East Indian leopard gecko Eublepharis hardwickii, a small stout species with a noticeably thick tail. Of course, as this gecko (like all others) is wholly harmless, in order to accommodate its identification as the bis-cobra the latter's dread reputation as a highly venomous creature must necessarily be nothing more than native superstition and folklore. The Mintons identified the hun khun as the closely related fat-tailed or common leopard gecko E. macularius.

Fat-tailed or common leopard gecko Eublepharis macularius (public domain)

Henry Newman noted that in the hotter, drier parts of India, 'bis-cobra' was a term applied to a rarely-seen, fleet-footed species of grey lizard. And that in Eastern Bengal, it is an elusive crested lizard occasionally spied in gardens and on walls.

In his recently-updated two-volume encyclopaedia of cryptozoology, Mysterious Creatures (2013-14), George Eberhart noted the Mintons' view. He also speculated that an alternative explanation for the bis-cobra is that it is a non-existent composite beast, created by locals combining (and sometimes confusing) reports of venomous snakes with non-venomous lizards.

By far the most commonly-held view as to the bis-cobra's identity today, however, is one that, ironically, had originally been suggested by a number of authors more than a century ago. In his earlier-mentioned book, for instance, EHA recalled how his captured bis-cobra gradually grew larger until within a few weeks it had developed into an unmistakeable 'iguana' (in India, a commonly-used colloquial, albeit zoologically-inaccurate, name for a varanid or monitor lizard). He concluded dryly:

Some people would jump to the conclusion that it was a young iguana to begin with. My butler would endure the thumbscrew sooner.

Similarly, in his above-documented Calcutta Journal of Natural History report from 1840, John Grant concluded that the specimen which he had pitted against the mouse was nothing more than a young goshamp – a local name in present-day Bangladesh and West Bengal for the common Indian (Bengal) monitor Varanus bengalensis. This species is widely distributed throughout the Indian subcontinent, and whereas adults are mainly terrestrial, juveniles are more arboreal, thereby explaining reports of tree-climbing bis-cobras. Their spotted patterning also matches morphological descriptions of the bis-cobra.

Photograph of EHA (public domain)

Moreover, writing in Beast and Man in India (1891), John Lockwood Kipling stated:

The large lizard, varanus [sic] dracaena, which is perfectly innocuous, like all Indian lizards, is called the bis-cobra by some.

Varanus dracaena is a synonym of Varanus bengalensis. Kipling actually owned a pet specimen of this monitor species, and whenever he held it he was invariably warned of its supposed deadliness by native observers.

Monitors were also confidently identified as the bis-cobra by L.S.S. O'Malley in his book Bengal, Bihar, Orissa and Sikkim (1917). In Eye in the Jungle (2006), acclaimed Tamil writer M. Krishnan affirmed that the dreaded bis-cobra has been shown by naturalists to be nothing more than young, harmless specimens of the common Indian monitor – a statement confirmed in the standard work on this varanid species, Walter Auffenberg's monograph The Bengal Monitor (1994). Today, therefore, the term 'bis-cobra' is treated merely as a synonym for the latter monitor.

The real bis-cobra - a juvenile common Indian monitor Varanus bengalensis (Jayendra Chiplunkar/Wikipedia CC BY-SA 3.0 licence)

All that remains to explain now are supposed cases (such as that of EHA's ghorawalla) in which a bite from a bis-cobra, i.e. a young Indian monitor lizard, caused a person's death. If such cases are indeed genuine, how are such deaths possible, bearing in mind that V. bengalensis is not venomous?

Various possibilities come to mind. For instance, in recent years it has been shown that certain varanids, notably the Komodo dragon V. komodoensis, do actually possess venom glands. Although the venom produced by them is not normally fatal to humans, someone exceptionally sensitive to it may conceivably suffer anaphylaxis in a manner comparable to the response of certain people to the venom in bee or wasp stings. And even if no venom is present, the bacteria present on the teeth of these lizards could readily infect a wound created by a bite from one, and thus induce septicaemia. Moreover, the superstitious fear generated by the bis-cobra may in itself be sufficient to bring about death by heart failure in someone bitten by a monitor lizard.

It may well be that isolated incidents involving one or more of these causes of death following a bite from a technically harmless lizard were sufficient to engender the tenacious myth of the lethal bis-cobra, especially among medically-untrained villagers. It would also explain the diversity of lizard species claimed by them to be the bis-cobra at one time or another. The ultimate result was a fascinatingly Frankensteinian creation of the deadliest lizard that never actually existed.

This ShukerNature blog article is excerpted from my book The Menagerie of Marvels: A Third Compendium of Extraordinary Animals.

SHERLOCK HOLMES AND THE SPECKLED BAND – AN UNKNOWN SPECIES OF REPTILE?

Reconstruction of the likely appearance of the Indian swamp adder, aka the speckled band (© Tim Morris)

According to a number of Sherlockian scholars, today, 6 January, is Sherlock Holmes's birthday - so it seemed a very appropriate day upon which to present the following ShukerNature investigation of mine.

During his numerous cases, the famous if fictitious consulting detective Sherlock Holmes, created by Sir Arthur Conan Doyle, encountered a number of extraordinary creatures – the hound of the Baskervilles, the giant rat of Sumatra (click here for my ShukerNature article re this monstrous rodent), an unknown species of worm that sent its observer insane, and an exceptionally venomous, enigmatic Indian serpent referred to obliquely by one of its victims as the speckled band. But does the latter snake truly exist, and, if so, what is it?

HOW SHERLOCK HOLMES DEFEATED THE SPECKLED BAND

First appearing in February 1892 within the Strand Magazine as a stand-alone Sherlock Holmes short story, 'The Adventure of the Speckled Band' is one of twelve that were then collected together and republished later that same year within a compilation volume entitled 'The Adventures of Sherlock Holmes'. (It was also adapted by Conan Doyle into a stage play called The Stoner Case, with the production opening at London’s Adelphi Theatre in June 1910.)

This particular story tells of how Dr Grimesby Roylott, a very aggressive medical doctor heavily in debt but with two heiress step-daughters, murdered one of them, Julia Stoner, using a most ingenious, undetectable modus operandi that he was now also secretly attempting to use upon his other step-daughter, Helen Stoner. If successful, he would retain all of their money. Although Helen does not realise that her own life is in imminent danger, she feels sufficiently disturbed by the mysterious death of her sister, who was heard to cry out "It was the band! The speckled band!" immediately before dying, to engage Sherlock Holmes to investigate.

Holmes, Watson, and Helen Stoner, depicted by Sidney Paget

Assisted by his faithful companion Dr Watson, it is Holmes who then discovers that Roylott had murdered Julia (and was now seeking to do the same to Helen) using an exceedingly venomous species of Indian snake referred to by Holmes as a swamp adder, whose blotch-patterned body was the speckled band that the doomed Julia's last words had succinctly described.

Sherlock Holmes striking out at the swamp adder, depicted by Sidney Paget

Happily, after hiding in Helen's bedroom they are able to thwart the deadly serpent, which, angered by Holmes's attack upon it with a cane, swiftly flees from whence it had come - back into the bedroom of its owner, Roylott. When Holmes and Watson then enter Roylott's room, they find him dead, with what looks at first like a speckled band wrapped around his head. Upon cautious, closer inspection, however, this proves to be the swamp adder, which in its enraged, still-agitated state had turned upon Roylott, killing him with a single lethal, fast-acting bite.

Waxwork of Dr Grimesby Roylott with swamp adder around his head, at London's Sherlock Holmes Museum (public domain, from Wikipedia)

THE INDIAN SWAMP ADDER – IN SEARCH OF AN IDENTITY

In the story, the swamp adder was referred to by Holmes as "the deadliest snake in India", but what exactly is a swamp adder? No known species of snake in India – or anywhere else, for that matter - is ever referred to by that particular name. Unfortunately, however, the story contains only the sparsest of morphological and behavioural details concerning this enigmatic serpent.

Its body is yellow, patterned with brownish speckles, and probably around 1 m long but fairly slender if it resembles a band and can wrap itself around a man's head. Its own head is squat and diamond-shaped, and its neck is puffed. Its hiss is said to be "a very gentle, soothing sound, like that of a small jet of steam escaping continually from a kettle", but according to Holmes its venom is so toxic that it kills in 10 seconds. Yet its fangs apparently leave such tiny, inconspicuous puncture wounds when it bites its victim that they were not noticed by the coroner who examined Julia Stoner's body. For according to a statement made by her sister Helen to Holmes, no marks had been found upon Jane by the coroner.

Down through the years, this intriguing reptilian mystery has engaged the attention of many scholars, of Sherlockian and herpetological expertise alike, with a number of different identities proposed for the perplexing Indian swamp adder.

IS THE SWAMP ADDER TRULY A SPECIES OF VIPER?

The most popular identity is the very venomous tic polonga or Russell's viper Daboia russelii, a large terrestrial species found throughout the Indian subcontinent. Due in no small way to its frequent proximity to human habitation, this infamous species is responsible for more deaths and incidents involving snake-bite than any other venomous snake in the entire region. Up to 1.66 m long, its relatively slender, brown-blotched, yellow-tan body does recall the 'speckled band' description for the mystifying swamp adder. Also, as its triangular head is distinct from its neck, when viewed at certain angles its head and the beginning of its neck can collectively yield a diamond shape.

Russell's viper (© gupt_sumeet/Wikipedia)

However, like that of all vipers, this species' venom is haemotoxic, which is relatively slow-acting compared to the much more rapid-acting neurotoxin produced by elapids. And far from being gentle and soothing in sound, its hiss is famously loud – among the loudest hisses produced by any species of snake. In addition, its preferred habit is dry, grassy, open terrain; it actively avoids humid, swampy, marshy areas. Clearly, therefore, the Russell's viper is unlikely ever to be referred to as a swamp adder.

Saw-scaled viper depicted in a painting from 1878

Two other viperid candidates that have also been proposed on occasion are the Indian saw-scaled viper Echis carinatus (also known as the little Indian viper) and the temple viper Tropidolaemus wagleri. However, the former species does not exceed 80 cm (and only rarely exceeds 60 cm), and does not possess either the speckled patterning or the diamond-shaped head of the swamp viper. Also, it is an inhabitant of dry, rocky terrain, not humid swamps. As for the temple viper: this pit viper species is bigger than the saw-scaled viper, with females growing up to 1 m long. It also exhibits a range of colour and pattern variations, but none of them includes that of the swamp adder. And, crucially, it is not native to India anyway (its distribution being confined to southeastern Asia).

Temple viper, green variety (© Bonvallite/Wikipedia)

Neither is the African puff adder Bitis arietans, yet this too has been suggested by some as a putative swamp adder. Quite apart from its fundamental zoogeographical difference, however, the puff adder is renowned for the loudness (as opposed to the gentleness) of its hiss, and for the savagery of its bite, whose fangs can cause severe physical trauma in addition to their envenoming effects. This is a very far cry from the very inconspicuous puncture marks attributed to the swamp adder.

Puff adder ready to strike

Another exclusively African species that has been considered is the rhinoceros viper Bitis nasicornis, named after its instantly noticeable horn-like scales on the end of its nose – features conspicuous only by their absence in the swamp adder's description!

Rhinoceros viper (© Dawson/Wikipedia)

Exit the puff adder and the rhinoceros viper.

COBRAS, BOAS, AND OTHER UNLIKELY SWAMP ADDER EXPLANATIONS

The common Indian cobra Naja naja is a much-touted elapid candidate for the swamp adder's identity, particularly by the late Richard Lancelyn Green and certain other Sherlockian scholars and devotees. Certainly, its neurotoxin would act more swiftly than the haemotoxin of any viper or adder. Nevertheless, it is difficult to conceive how so familiar and distinctive a snake as this one, perhaps the best known serpent species in all of India, could possibly be one and the same as the mysterious swamp adder. True, the latter's puffed neck may be an allusion to the cobra's hood (or at least a cobra-reminiscent neck expansion), but the Indian cobra lacks the characteristic speckled patterning of the swamp adder, and its head is not diamond-shaped. In fact, it looks nothing remotely like any type of adder or viper.

Indian cobras and snake charmers, depicted in a lithograph from 1890

Even more implausible ophidian identities that have been raised at one time or another include the decidedly non-venomous, non-Asian boa constrictor Boa constrictor; the extremely venomous but irrefutably Australian taipan Oxyuranus scutellatus; and a species of krait.

Fundamental zoogeographical differences aside, the boa constrictor notion no doubt stems from a suggestion that Conan Doyle was inspired to write his story having read a story entitled 'Called on by a Boa Constrictor: A West African Adventure', which had appeared in Cassell’s Saturday Journal, published in February 1891. Staying in a ramshackle cabin belonging to a Portuguese trader, the narrator reveals his horror at being woken by a massive snake dangling over him. Paralysed by fear, he cannot cry out, but he spots a bell hanging off a beam within reach. Although the cord to ring it has rotted away, the narrator discloses how he manages to summon help by hitting it with a stick.

Boa constrictor

Nor is this the only link between the speckled band mystery and a species of constricting snake. In his stage production of this story, The Stoner Case, Conan Doyle cast an African rock python Python sebae as the speckled band. Unfortunately, this particular snake did not excel in the role. Conan Doyle later wrote:

"We had a fine rock boa [sic] to play the title-rôle, a snake which was the pride of my heart, so one can imagine my disgust when I saw that one critic ended his disparaging review by the words, "The crisis of the play was produced by the appearance of a palpably artificial serpent." I was inclined to offer him a goodly sum if he would undertake to go to bed with it."

As for a krait: it is true that certain species are Indian, all are venomous (some extremely so), and they may be encountered in damp areas. However, they differ dramatically from the speckle-patterned swamp adder with its squat diamond-shaped head by virtue of their boldly striped markings and their sleek, slender head.

Banded krait, depicted in a painting from 1878

Kraits are also extremely timid, often preferring to conceal their head amid their coils, drawing attention away from it by vigorously twitching their tail instead, thus readily contrasting with the swamp adder's active, undisguised aggression.

Of course, there is the remote, but not impossible, prospect that the swamp adder is not a snake at all...

WHEN IS A SNAKE NOT A SNAKE? WHEN IT'S A LEGLESS LIZARD?

Certainly, there are various peculiar behavioural characteristics claimed for the swamp adder that cause problems when attempting to reconcile it with any species of snake. In 'The Adventure of the Speckled Band', the swamp adder reaches its victim, Julia Stoner, by crawling through a ventilation shaft linking her bedroom with that of her murderous step-father Roylott next door, and then down a rope pull hanging directly over the bed in which she is sleeping. After it has bitten her, the snake crawls up the rope again and back through the shaft, in response to Roylott (in his bedroom) having alerted it by whistling to it!

First and foremost: unless it were an exceptionally adept arboreal species, would the swamp adder be able to climb up a vertical length of rope? And secondly: as snakes are famously insensitive aurally to airborne vibrations, how could it possibly be able to hear Roylott's whistling?

Consequently, there has been speculation that the swamp adder is not a snake at all, but conceivably a legless or near-legless species of lizard, belonging to the skink family. There are indeed several species of skink fitting this description, and which therefore do appear remarkably serpentine on first glance, especially to non-specialist observers. Some such lizards, moreover are native to India.

Chalcides chalcides, a near-limbless skink

And skinks, unlike snakes, can definitely hear airborne vibrations. Whether they are adept at climbing up and down vertical ropes is another matter, but in any case this otherwise ingenious non-ophidian identity is fatally scuppered by the incontestable fact that skinks are entirely non-venomous. Consequently, if a skink bit someone, they would not be poisoned by it.

The only sensible conclusion that can be drawn from this article's analysis of the varied candidates on offer is that the swamp adder is an entirely fictitious, invented creature that Conan Doyle created specifically in order to supply his story with a supremely formidable reptilian opponent for pitting against Sherlock Holmes – an ophidian Moriarty, no less. Aspects of its appearance may well have been inspired by real snakes, such as the Russell's viper's body colouration and markings, and the rapid action of the cobra's neurotoxin, but the swamp adder has no basis in reality as a valid, discrete species in its own right.

Russell's viper, depicted in a drawing from 1878

However, this is not quite the end of this literary serpent's identity crisis. There is still one more identity to consider, the most astonishing of all – not only because of its particular nature but also because of where (and how) it appeared within the scientific literature.

SWAMP ADDER AND MONGOLIAN DEATH WORM – ONE AND THE SAME CREATURE?

In a previous ShukerNature article (click here), I documented an extraordinary mystery beast said to inhabit the Gobi Desert and known as the Mongolian death worm. According to the nomads inhabiting this vast expanse of sand, the death worm can spit forth a deadly, corrosive venom, and can also kill instantly if touched by a mechanism that sounds uncannily like electrocution. No specimen of this reputedly lethal animal has ever been made available for scientific analysis, and it may well simply be folkloric, or even if genuine merely a harmless amphisbaenian or similar reptile whose murderous talents owe more to local superstition than to physiological capability.

Reconstruction of the likely appearance of the Mongolian death worm (© Ivan Mackerle)

In 1956, however, the death worm was sensationally linked to the swamp adder as the latter's bona fide identity. Not only that, it was even given a formal scientific name. The publication in which all of this appeared was a very comprehensive 238-page monograph of the lizard family Helodermatidae, which houses those two famously venomous New World species, the Gila monster Heloderma suspectum and the beaded lizard H. horridum. Published in no less august a scientific journal than the Bulletin of the American Museum of Natural History, and entitled 'The Gila Monster and Its Allies', it was authored by renowned herpetologists Drs Charles M. Bogert and Rafael Martín Del Campo, and as would be expected from such authors writing in such a journal, the paper was totally scientific and serious throughout – or was it?

Gila monster

Tucked away on pages 206-209, in a section entitled 'Hybrid Origin', was a mind-boggling claim that according to a paper by snake authority Dr Laurence M. Klauber, a hybrid creature had been successfully produced in a laboratory in Calcutta, India, by crossbreeding cobras with Gila monsters! Not only that, some of these astounding hybrids had subsequently escaped, with various of their descendants yielding the allegedly highly venomous Indian lizard called the bis-cobra (featured in a forthcoming book of mine), and other descendants yielding the Mongolian death worm in the Gobi Desert!

Moreover, and equally dramatic, this selfsame hybrid was also claimed to be the identity of the swamp adder in Conan Doyle's Speckled Band story. A quadrupedal lizard with the venomous potency of a cobra would, in the opinion of Klauber, reconcile all of the problems faced when attempting to identify the swamp adder with any of the more traditional identities that have been proposed.

Accordingly, in their monograph Bogert and Martín Del Campo put forward an official binomial name for this hybrid, which was clearly now breeding true and therefore, they felt, fully deserved one. They dubbed it Sampoderma allergorhaihorhai – 'Sampoderma' combining 'samp' (a Hindustani name for 'snake') and the Gila monster's generic name, Heloderma; and 'allergorhaihorhai' being a name applied by the Gobi nomads to the death worm. They even included an ideogram of the hybrid's appearance.

Ideogram of Sampoderma allergorhaihorhai (© Derry Bogert/Bulletin of the American Museum of Natural History - reproduced here on a strictly non-commercial Fair Use basis for educational/review purposes only)

Needless to say, however, the concept of successful hybridisation between a cobra and a Gila monster is so outlandish that there was clearly more – or less – to the claims of Bogert and Martín Del Campo than met the eye, as a closer study of this particular section of their monograph soon revealed. (Moreover, the bis-cobra is also a red herring, figuratively if not taxonomically, because in reality it is a harmless varanid that superstitious folklore has conferred all manner of venomous traits upon.) For although Klauber was indeed a real-life herpetological authority and his paper regarding the hybrid also existed, it had not been published in any scientific journal but instead within an issue from 1948 of the Baker Street Journal.

This was a periodical devoted entirely to the fictional world contained within the stories of Sherlock Holmes, and included much imaginative and entertaining but entirely theoretical speculation and extrapolation regarding various aspects of these stories' plots, characters, etc. And indeed, in his paper Klauber refers to Holmes, Watson, and the nefarious Dr Roylott as real persons, naming Roylott as the creator of the cobra x Gila monster hybrid. In short, it was all entirely tongue-in-cheek, not to be taken in any way seriously.

As this is instantly apparent from reading Klauber's paper, why, therefore, had Bogert and Martín Del Campo included the fictitious hybrid in a sober, ostensibly factual manner within their otherwise entirely literal, highly authoritative monograph? According to Daniel D. Beck writing in his own major work, Biology of Gila Monsters and Beaded Lizards (2004), it was a prank by Bogert that was meant to poke fun at one of his "stodgy" colleagues at the American Museum of Natural History.

Beaded lizards – closest living relative of the Gila monster

Whatever the reason, there is no doubt at all that equating it even in jest with the Mongolian death worm yielded for the dreaded Indian swamp adder (aka the speckled band) an identity so extraordinary that even the great Sherlock Holmes himself may well have been hard-pressed to deduce it!

Sherlock Holmes, depicted by Sidney Paget

NB - all non-credited illustrations included in this ShukerNature article are (to the best of my knowledge) in the public domain.