A flesh-eating worm from Argentina has wriggled its way into Britain - and is set to cause havoc for farmers and gardeners, writes Mark Waghorn.

The killer creepy-crawly grows up to three inches long and has hundreds of tiny eyes along its whole body.

It hunts snails and earthworms - putting the UK's indigenous population at risk.

The damaging pest could wipe out up to a fifth of our most vital invertebrates.

The slimy brown flatworm, known as Obama nungara, was accidentally imported from South America and is now harming local wildlife.

It has spread rapidly throughout France adding to fears it has already crossed the English Channel in numbers - which will alarm the agricultural industry.

The crisis is being fuelled by the international trade in plants. Adult worms and cocoons can easily travel in pots.

The worm is now present in 72 out of 96 French metropolitan districts - an area representing 75 per cent of the country.

Lead Professor Jean-Lou Justine, a zoologist at the Natural History Museum in Paris, said: "To date, the presence of Obama nungara has been occasionally recorded from several countries in Europe, including Spain, Portugal, UK, Italy, and Belgium.

"However, in none of these countries has a study of the extent of the occurrence of O. nungara been performed."

The latest observations mainly by 'citizen scientists' are the first of their kind - and include 530 verified records received from 2013 to 2018.

Professor Justine said: "The extensive distribution of the species and its reported local abundance, combined with its predatory character, make Obama nungara a potential threat to the biodiversity and ecology of the soils in Europe.

"O. nungara is the most threatening species of all invasive flatworms present in Europe."

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The worm was first seen in Europe on Guernsey in 2008, but has spread through France and into Spain and has also been confirmed at a number of locations in the UK.

Professor Justine said: "The origin of the invasion by O. nungara is likely to be via the international trade of plants, since adult flatworms and cocoons can easily travel in potted plants."

Land flatworms are predators of soil animals, including earthworms and molluscs.

This endangers the biodiversity of native animals and soil ecology, although the extent of impact has yet to be analysed.

It has been suggested O. nungara will reduce earthworm numbers in the UK by up to 20 per cent - judging by the experience with the invasive New Zealand flatworm.

Earthworms are essential for keeping soil healthy - both in gardens and in crops for agriculture.

Their loss makes soil less fertile and more prone to flooding as worms digging holes help drainage.