Two banded file snakes were fucking on the flat off the northern rim of Pulau Semakau, where the perimeter bund of a bulging landfill meets a wall of artificially planted mangroves, one evening when their union was interrupted by a gaggle of explorers who stalked and stumbled over the shore, torch in hand and hopes in thrall to a day of late tidings. The male, who kept his coils in a tight spiral around the nether regions of his mate, was a clean-living fellow, though his stripes were rough on the edges and had little of the sheen of a recently moulted individual. The lady, to her credit, was a tramp who had allowed her hide to hang loose and become a habitat for green filaments.
A snake at sea but confined, it seems, to the zone below the pools of bockadams and before the reefs of true sea serpents, Acrochordus granulatus may venture, and even thrive, in freshwater reservoirs via tidal gates or estuarine channels. Locally, they may be encountered on the fringes of untamed islets such as Pulau Sekudu or the skirted slopes and seagrass beds of Pulau Semakau, where their glum and sluggish disposition belie an ability to intercept, constrict and swallow good-sized gobioids and goatfish, which let their guard down before the jaws of a reptile whose low metabolic rate allows it to remain submerged and still for long periods. As with other squamates, the males wield paired hemipenes that are extruded from a cloaca at the base of a surprisingly short tail. With his lower torso suitably entwined around the female, the male everts one of his hemiphines, which latches onto the inner walls of his mate to facilitate prolonged coitus while the unused hemi-organ swings freely. This physical bond probably accounted for the reluctance of the pair to break loose and cut short their consummation, even though they failed to consult each other on which direction to take in sidestepping the spotlight.
Keen eyes are not an asset for file snakes, which hunt in murky pools and plunge their heads into dim lairs in search of demersal prey. Yellow-lipped sea kraits, on the other hand, swim in clear waters, using their paddle-like tails to propel themselve through seaweed and benthic growth as they pursue eels and other fish. For all the power of their bite, these elapids are vulnerable to predators such as sea eagles, sharks and even swimming crabs – their eyes are hence attuned to detecting motion, be it by food or foe and, as if to make up for an anatomical chink in their armour, their tails have evolved photoreceptors, prototypic eyes as it were, that tell the animal, during attempts at taking cover, if its rear end remains in sight and at risk of flightful talons. Snakes at sea, it seems, still slither with secrets that suffer not the soft stabs of intertidal missions at shining a harsh, hollow light at beasts we love to hate and never hope to know.