I used to imagine that whip snakes were named after some obscure godlet from ancient Egypt, perhaps a minor scion of Apep who evaded the claws of Bastet, or a cousin of Wadjet, whose visage rose from the crowns of pharaohs, a rearing expression of the right to rule and the rule of Ra, in whose name and blood temples, tombs and four-sided towers were erected by royal decree in a valley of dreams. Or an impotent worm allied to the beast that saved Cleopatra from shame, the bosom fiend whose bite was blessed by the bard. Another hypothetical progenitor was the serpent, Ouroboros, who secures in her jaws the tip of her tail and the fate of mittel earth, which in a moment of ophiophagous slackness would abandon its futile loops and enter a spiral of cosmic decay.
Linnaeus was probably the first Westerner to bestow the name Ahaetulla to a snake, but in a time when labels were sloppy and sources credulous, the moniker was given to a colubrid originating from the New World. The Swede also offered no description to accompany his summary dispatching of Coluber ahaetulla as a species from "Asia America" – the latter region a result of misbundled specimens – an omission that befuddled later herpetologists who variously applied the binomial to the snake now known as Leptophis as well as a far flung creature that underwent rounds of taxonomical confusion before emerging as Dendrelaphis pictus.
A German biologist, Johann Heinrich Friedrich Link, then elevated Ahaetulla to a rank that included the painted bronzeback as well as the Malayan whip snake, but these reptiles were rightly regarded as sufficiently different to warrant a further split that assigned mycterizans to Dryophis (literally 'tree snake), until the gods of zoological nomenclature decreed that Dryophis, being a junior synonym to Link's coinage, should be ditched for Ahaetulla. Meanwhile, Dendrelaphis, being the oldest available genus, would apply to arboreal serpents with bright eyes, not overly slender torsos, polished dorsa and swift dispositions. Linnaeus' holotype retained its specific name, but the parrot snakes of Latin America had long diverged, in lineage and title, from Asian colubrids.
Linnaeus offered little explanation as to the inspiration for his missnake, but one of the bodies in his original bag may have arrived from an island that was a major pitstop for traders between Europe and the Far East, and which became a byword for discoveries of a not unpleasant nature. In Sinhalese, 'ahatulla' or 'ehetulla' is used to denote a legless creature with the purported ability to pluck out one's eyes. This impression, more imagined than effected, may stem from the snakes' habit of basking at the fringes of dense forests, draped over foliage at or slightly above chest level. Confronted by naked apes, some individuals choose not to bravely retreat – coils wound, forequarters dilated and exhibiting a patchwork of chequered excitement, the snake may feint a strike or two, which are likely to be aimed at facial features that draw a blink and prompt a recoil from onlookers who prize their peepers. Lacking lids, the ehetulla can only mock the gaze of its beholders, following their stares with a stereoscopic rejoinder, the binocular upshot of horizontal pupils and a rut that runs from the eyes to the tapered snout, and forked overtures that suggest peril to some but serve simply to give the snake a taste of its perimeter and a sense of what's to come. It's unclear if the eyebiters fare better in Ceylon, but in isles of unquestioning minds and coarser appetites, every emerald serpent is deemed a mortal threat and dispatched with summary strokes.
Sri Lanka is home to two species of whip snakes: Ahaetulla nasuta, which is commonly encountered on low bushes and ranges in colour from green to brown to buff to pink, and Ahaetulla pulverulentes, an uncommon brownish creature known locally as 'hena kandaya', whose very shadow causes lameness or paralysis. The former, which is reported to include fish in its diet, used to share its name with a congener from Sundaland, but mycterizans now refers to a smallish ehetulla restricted to Java, Sumatra and the Malay Peninsula, including Singapore. Possessing eyes of extraordinary power, Ahaetulla mycterizans is a much rarer beast than prasina, which occurs in a diversity of habitats from unruly gardens to mangrove woods. Even compared to the latter, the optics of mycterizans dominate the face, reaching the ridge of the brow and leaving little space for the cheek, while its snout is markedly convex rather than flat or depressed and the throat is cream or white instead of green, yellow or buff. Confined to mature forests in the vicinity of shaded streams, the big-eye green whip snake remains safely out of sight for the most part, but there is little it can do to flee the danger zone of lines that seek to run under the law and rip through what remains of Singapore's primeval heartland to spare naught, suffer every room for error and save a minute or two.