A rare giant skeleton of a dinosaur which last roamed Earth more than 150 million years ago was bought for the Natural History Museum of Denmark, it has confirmed.

Mystery surrounded who had bought the 55ft specimen of the long-necked Diplodocus longus when it fetched £400,000 at an auction in West Sussex last month.

But now the Natural History Museum of Denmark has confirmed it acquired the striking female skeleton, nicknamed Misty, following a donation from the Obel Family Foundation.

Museum director Morten Meldgaard said: "To own a giant dinosaur is, of course, the dream of any natural history museum.

"In order to understand the nature and the world we live in, we have to understand the past. And more than anything else, a dinosaur is an object that connects us with the distant past."

The skeleton was found almost completely intact in 2009 by the sons of renowned palaeontologist Raimund Albersdoerfer near a quarry in Wyoming in the United States.

Mr Albersdoerfer had been taking part in an excavation at the privately-owned quarry when he sent his sons to dig in an area nearby "to get them off his back".

To their father's astonishment, Benjamin and Jacob returned to him at the end of the day to say they had found an enormous bone.

Nine weeks later, Mr Albersdoerfer's team dug out Misty, and she was painstakingly prepared at a leading fossil laboratory in Holland before being assembled in the UK.

The skeleton was auctioned as part of the Evolution Sale, curated by natural history expert and author Errol Fuller, at Summers Place Auctions in Billingshurst, West Sussex.

Established in 1956, the Obel Family Foundation supports activities in research and education, art and culture and health and social objectives.

Its chairman, Christen Obel, said: "I think it's quite obvious and right that the Natural History Museum of Denmark should own a dinosaur.

"So when we suddenly had the opportunity to give the museum this early Christmas present, we jumped at the chance.

"Misty is an iconic object that fascinates us, and the dinosaur will certainly create value for the museum for many generations to come."