The Mongolian death worm

Gobi herders’ folklore; likely a worm lizard, never found

Mongolian herders call it the olgoi-khorkhoi, the large intestine worm, and the name tells you what it looks like: a fat, dark red, sausage-shaped thing up to a metre long, with no head or legs that anyone can make out, said to live under the sands of the southern and western Gobi. It travels underground, raising waves of sand that give it away, and comes to the surface rarely, some say after rain. It is credited with killing at a distance, by spitting a corrosive venom or by an electric discharge, and locals give any one lying on the surface a wide berth.

Western readers heard of it from the American palaeontologist Roy Chapman Andrews. In 1922 the Mongolian prime minister, Damdinbazar, described it to him as a sausage about two feet long, so poisonous that merely to touch it meant instant death. At a gathering of officials, Andrews wrote in On the Trail of Ancient Man in 1926, none of those present had ever seen the creature, but all firmly believed in it and described it minutely. Andrews himself did not believe in it.

Others went looking. The Russian palaeontologist and science fiction writer Ivan Yefremov wrote a story about it in 1944, and while hunting fossils in the Gobi between 1946 and 1949 heard the legend many times but met nobody who claimed to have seen one. In 1990 and 1992 the explorer Ivan Mackerle searched with a motor-driven thumper, inspired by the sandworms of Frank Herbert's Dune, and even small explosions. Richard Freeman of the Centre for Fortean Zoology came back empty-handed in 2005, as did a television series in 2006 and 2007 and the New Zealand reporter David Farrier in 2009, who was told that sightings had peaked in the 1950s.

The likeliest answer is a reptile. In 1983 locals who said they had seen olgoi-khorkhoi were shown a Tartar sand boa and agreed it was the same animal, and Freeman and the biologist Karl Shuker favour a worm lizard, a burrowing, limbless reptile that can look very like a large worm. As Benjamin Radford of Skeptical Inquirer points out, anything living in the Gobi would have to be a vertebrate with a spine, and a breeding population would need tens of thousands of animals, none of which has ever turned up. The worm lives on in the Graboids of the Tremors films it is said to have inspired.