U.S. researchers say they\'ve discovered what may be the earliest dinosaur, a small creature from about 10 million years before more familiar dinosaurs. About the size of a Labrador retriever but with a 5-foot-long tail, Nyasasaurus parringtoni suggests the dinosaur lineage appeared 10 million to 15 million years earlier than fossils previously showed, originating in the Middle Triassic rather than in the Late Triassic period, the University of Washington reported Tuesday. \"If the newly named Nyasasaurus parringtoni is not the earliest dinosaur, then it is the closest relative found so far,\" postdoctoral biology researcher Sterling Nesbitt said. \"For 150 years, people have been suggesting that there should be Middle Triassic dinosaurs, but all the evidence is ambiguous,\" he said. The fossilized bones examined by the researchers to identify the new species were collected in the 1930s in Tanzania and are part of the collection at the Natural History Museum in London. \"What\'s really neat about this specimen is that it has a lot of history,\" Nesbitt said. \"Found in the \'30s, first described in the 1950s but never published, then its name pops up but is never validated. \"Now 80 years later, we\'re putting it all together.\"