A new species of monkey with a distinctive blue rear end has been identified in Africa, researchers have said.

The species, known locally as the lesula, was discovered after a young female was seen kept captive at the home of a primary school director in the Democratic Republic of Congo in 2007.

The young animal resembled an owl faced monkey (Cercopithecus hamlyni) but the colour of its rear end was different to that of any known species, the researchers writing in the journal PLoS ONE said.