Earthworms can live for up to eight years - that is, unless they're as big as a snake and need to be euthanised in the name of science.

Dave the giant worm was spotted by Paul Rees wriggling around in his vegetable patch in Widnes, Cheshire. The gardener was so impressed with its size he retrieved the creature from the soil and alerted researchers at the Natural History Museum.

But not before his stepson George gave the slippery animal its moniker.

Dave was carefully packed off to the museum, where he was measured at 40 centimetres long and weighed in at 26g - making him three times longer and five times heavier than the average garden earthworm.

Excited researchers at the museum filmed their first meeting with Dave, showing the curious Lumbricus terrestris sliding around on scientist Emma Sherlock's hand.

"It's so cool," a man's voice is heard to say.

"He is amazing," Sherlock responds.

But then Dave had to die.

A spokesman for the Natural History Museum has assured ITV News that the process of putting Dave to sleep was "painless".

Waiting for Dave to expire naturally would have meant his body could not be preserved in optimum condition.

Before Dave (RIP), the country's largest earthworms were found on the Scottish island of Rum, where one grew to to 39.6cm last year.

However, Scotland's gargantuan worms could not match Dave for girth, with the heaviest weighing just 12.6g to Dave's 26g.

Experts believe the earthworms of Rum flourished because of a lack of predators and rich soil.

How Dave got to be such a size in Cheshire remains a mystery.

"With worms this size Paul must have an incredibly fertile and well-drained veg plot with decaying matter quickly recycled back into the soil," Sherlock said. "Earthworms are incredibly important to keep soils healthy."

Sherlock, who chairs the Earthworm Society of Britain, added: "I look forward to seeing if anyone can find an even bigger example by taking part in the Earthworm Watch survey this autumn."

Earthworm Watch is a survey of earthworms and soil quality run by the Natural History Museum and the Earthwatch Institute in association with the Earthworm Society of Britain.

But beware, successful applicants may not be around for long...