They might look like fun guys but they are in fact 'a new species for the world' – and they have been found in Norfolk.

The curious man-shaped appearance of earthstar fungi has long fascinated naturalists, with Norfolk the only place in the country where all 17 species have been recorded.

But that has just become 18 after the discovery of a brand new species which was collected at Cockley Cley, in west Norfolk, which differed slightly from the rare rayed earthstar.

It was discovered back in 2000 by Jonathan Revett, a member of the Norfolk and Norwich Naturalists Society, while he was out rambling in the woods but was initially thought to just be a variant.

But recent re-examination and DNA sequence analysis has enabled mycologists in Spain to describe it as an, until now, unknown species which has been given the name geastrum britannicum to recognise that it has only been found in Britain.

Since Mr Revett's original find, three more specimens have been collected in Norfolk and the fungus has also been found in Hampshire and the Welsh Borders.

Carl Chapman, of Norfolk-based Wildlife Tours and Education, said: 'This is riveting stuff. This is not just a new species for Norfolk – this is a new species for the world.'

The species has been revealed 15 years after it was first collected because samples of the fungus were also sent Kew Gardens who were contacted by mycologists in Spain who were looking to conduct DNA analysis.

Mr Chapman said: 'They were doing the work and requested some samples of this fungus and found the DNA was different.'

Tony Leech, chairman of the Norwich and Norfolk Naturalists Society and Norfolk's Fungi recorder, said it was a very rare find.

He said: 'This is not just a new species of fungus for Norfolk or for Britain. It is new to science.'

It is not the first time a rare fungus has been found in the county.

In 2013 oak polypore (buglossoporus pulvinus) was found growing out of an oak tree at Wymondham College. It is only the third time the fungus has been recorded in Norfolk.

Speaking in September 2013, Andy Gardiner, senior science technician who noticed the fungus as he was driving home, said: 'I am always on the lookout for things and I could see fungus growing out of a tree. I noticed it because it was a bright yellow colour. We thought it might be an oak polypore and sent a photo to the county recorder.

'We are going to have to put some kind of mesh over the top to stop the children getting to it. It's quite close to the football pitches.'

In June 2012, a rare fungus with potential medical benefits was rediscovered on pony dung on heathland in Thetford Forest.

Previously, it was only known to exist in the New Forest and researchers are baffled by the discovery made during a routine inspection in Thetford Forest.

Forestry Commission ecologists said they were delighted because its presence also shows heathland restoration and grazing by ponies can create the perfect conditions for the fungus. The nail fungus, called poronia punctata, had not been recorded in the county since 1944.

And in 2010 it was believed the hoof fungus, a rare tree fungus which existed in Norfolk thousands of years ago, might be making a comeback after there were several sightings in the county.

Have you made a rare find? Email peter.walsh@archant.co.uk

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