Nanotyrannus lethaeus was a fast, agile predator distinct from T. rex, with longer legs, stronger arms and a body built for ...

Debate kicked off in 1988 when a single small tyrannosaur skull discovered four decades earlier was given its own species ...

A new analysis of a fossil unearthed in 2006 provides a fresh line of evidence that a separate tyrannosaur lineage called Nanotyrannus lived alongside the famous T. rex ...