A team of Chinese researchers said they have discovered the world's oldest primate fossil, state media reported.

Archicebus achilles was about the size of a large mouse. By digitally reconstructing the two divided halves of the fossil, the researchers have been able to examine it in detail, from its small eyes to its large, monkey-like feet, CCTV reported.

State-run People's Daily newspaper reported that Archicebus achilles was discovered in 2002 in China's central Hubei province, in rocks deposited roughly 55 million years ago, but it has taken more than ten years of analysis for scientists to declare it as the world's oldest known primate fossil.

The scientists say the fossil represents a point in evolution when primates diverged into two groups -- tarsier primates and anthropoids -- whose modern descendants include monkeys and humans.

Archicebus's discovery now raises new questions about when and where the evolution of modern primates began, CCTV said.