Oops, it looks like there’s been a bit of a mix up with the humble leech in medical research!

In the slimiest and perhaps costliest case of mistaken identity in modern biology, hundreds of scientific papers and years of research could be thrown into doubt, for they may have been based on experiments carried out on the wrong leech

It’s the wrong leech Gromit, and they’ve gone wrong! (Apologies to The Wrong Trousers)

“What has been sold and used as Hirudo medicinalis is usually another species, Hirudo verbana,” said Dr Siddall, who led an international team of researchers in examining dozens of specimens procured from leech farms in Europe and the United States. “Indeed, we have never received a true medicinalis from a commercial supplier,” he said, adding a few leeches from a third species, H. orientalis, from Turkey or Azerbaijan, may also have crept into the mix.

There is an upside to this (asides from the increasing volume of medical papers as they try and correct their previous research and try and work out what compound came from which species):

“With three species rather than one, there may three times as many interesting compounds to be discovered and harnessed,” he said.