A Chinese dinosaur scientist has expressed his disappointment and concern at the sale of a rare fossilized dinosaur nest for US$420,000 at an auction in Los Angeles.

The unusually well-preserved 65 million-year-old dinosaur nest containing fossilized eggs was sold by auction house Bonhams & Butterfields on Monday.

Before the auction, Xing Lida, a dinosaur expert with the Chinese Academy of Sciences, appealed to Bonhams not to auction the fossil, which he believes to have been smuggled out of China.

US media have reported that the nest was unearthed in south China's Guangdong Province in 1984. The nest is believed to be that of a raptor.

The nest contains 22 unhatched eggs arranged in a circular pattern around the edge. Embryonic remains were uncovered in 19 eggs and one egg was removed for study. Some eggs were so well-preserved that the embryo curled inside was still visible.

Bonhams has refused to reveal the identity of the buyer and the mystery surrounding the whereabouts of its new home has concerned scientists. Earlier reports said that the original collector had hoped the fossil could be bought by a museum at the auction. But experts had warned that due to the current fervor among private collectors and limited funds of museums, the fossil was most likely to fall into private hands.

"I am worried about the fossil's fate since many collected articles have disappeared with a change or death of the owner," Xing said.

"The well-preserved dinosaur embryos are rare and many Chinese scientists have only seen such fossils in pictures. The fossil will lose its scientific value in the hands of private collectors," he said.

Gerald Grellet-Tinner, a dinosaur expert at the South Dakota School of Mines and Technology, told US media that such a fossilized nest was a "bonanza" find that could tell scientists a great deal about dinosaur growth and development.

He argued the nest should be housed in a museum in China, where it was discovered, and not in private hands.

The theft and smuggling of fossils out of the country is a serious problem in China. Smugglers have often broken fossils to make them easier to conceal and carry.

Xing said that apart from a few local regulations China had no law on the protection of fossils. He said he and fellow Chinese experts were urging the authorities to draft new laws to increase fossil protection.

(Xinhua News Agency December 5, 2006)