Gerald Mayr of the Forschungsinstitut Senckenberg in Frankfurt, Germany, and colleagues at the Wyoming Dinosaur Center in Thermopolis, say their findings strengthen theories that birds descended directly from dinosaurs.

The 150 million-year-old fossil, found in Germany's Bavaria region, suggests the magpie-sized creature could hyperextend its second toe in a dinosaur-like way, the researchers report in Friday's issue of the journal Science.

"By all measures, it is a treasure," Peter Dodson of the University of Pennsylvania was quoted by Science as saying.

The feathered fossils were long believed to be representative of the first birds and this one now links Archaeopteryx to dinosaurs.

"Contrary to virtually all existing reconstructions of Archaeopteryx, the new specimen shows that the first toe was not fully reversed as in extant birds," the researchers wrote.