Not so long ago I was listening to a tokay gecko do his loud, tokay thing (a call sounding much like ‘to-kay, to-kay’ – repeat to fade – hence the name), when a Khmer friend asked me if I knew about the ‘liver snake.’ No I did not. What was this creature?

Apparently, when the tokay’s liver gets swollen it cannot make any noise and at this point a helpful snake comes, slides inside the willing tokay’s mouth and eats a piece of its liver. Then it leaves and the relieved tokay goes about its noisy business.

Naturally, I asked my friend if he was joking. He insisted he wasn’t. In fact, two more people immediately backed up his story. But how can the tokay survive, I asked? Does this process not hurt it? How does the snake even fit down its throat (it’s a very small snake, apparently) and how does it know it’s needed? Does the tokay send out a silent distress signal? Still cynical, I mentioned this story to a Khmer teacher friend of mine a couple of nights later, fully expecting him to burst out laughing at the silly barang taken in by an old wives tale. But he too, solemnly insisted it was true – repeating it almost word for word.

And so it continued, next a work colleague telling me she had seen it with her own eyes as a young child. “My father said come, look. I saw them together… Then the tokay ran away.”

This gruesome yet fascinating tale of reptile symbiosis in Siem Reap had me hooked and I turned to the internet for more verification. Unsurprisingly, no National Geographic or BBC Natural History report leapt out at me.  No “Snake Gorges on Gecko Liver” tabloid headlines.

I did however find many forums, written for the most part by barangs, discussing the ‘myth’ of the liver snake, which I compared to the absolute conviction held by Khmers.

Delving into the realms of academia, I contacted Bryan Stuart, the curator of Herpetology at North Carolina Museum of Natural Sciences, who was unequivocal in his response.

“No vertebrate has a liver that swells up and needs pieces torn off of it,” he said, adding, “Tokays have an aggressive disposition and would never tolerate such a thing, and no snake feeds by tearing pieces off of a larger animal (except for a Southeast Asian crab-eating snake).

“The myth could have started when someone saw a tokay consuming a small snake that was still wiggling and emerging from the tokay's mouth.”

Timo Hartmann from the Herpetology department at The Zoological Research Museum Alexander Koenig in Germany, agreed that a tokay would never allow a snake to crawl into its mouth and feed on its liver. He explained, “If so, the tokay would die soon because of bad internal bleeding.”

The Zoological Park Organization of Thailand also cast aspersions on the phenomenon, painting a less harmonious picture – not so much a collaborative partnership as a schoolboy bully stealing sweets off a younger boy.

The organisation’s website says that if the alleged ‘liver snake’ – in reality the golden tree snake – cannot find food it will sometimes, “Force and steal food from the gecko so people misunderstand that the green snake eats the gecko’s liver. But, actually, the green snake tightens the gecko’s body so the gecko opens its mouth and then the snake steals and eats the bits of meats or insects in the gecko’s mouth or on the gecko’s teeth. The snake does not get into the gecko’s mouth to eat the gecko’s liver.”

But Timo Hartmann also shot down Zoological Park Organization’s theory that the snake was putting the squeeze on the tokay to get it to disgorge its food.

“This is also nonsense," he stressed, “Because the snake only feeds on lizards.”

Hartmann added, “On the other hand, big tokays would also feed on a small snake because they more or less feed on everything fitting into their big mouths. But I highly doubt tokays will get any juvenile snakes to eat them.

"So all in all I am sorry to tell, there is no symbiotic relationship for a snake and a tokay.”

Whereas the Zoological Park Organisation Thailand added to the confusion about which creature may or not be eating, by saying, “If the gecko’s size is not so big, the snake may eat the whole body of the gecko.”

And there you have it. But the good news is, according to Phnom Kulen National Park rangers, when a tokay calls more than five times, it’s good luck.