A tribe of apes living in remote forests in the northern Democratic Republic of Congo are unusually large chimpanzees, not a new species of giant ape or a chimp-gorilla hybrid, New Scientist says.
Zoologists became excited after people living around Bili, a town about 200 kilometres (120 miles) east of the Ebola River, recounted tales of seeing huge ferocious apes with a taste for killing lions.
From photographs, the creatures were estimated to weigh about 100 kilos (220 pounds) and their footprints, at up to 34 centimetres (13.6 inches), were longer than a gorilla's.
But a year-long hunt by Cleve Hicks and colleagues from the University of Amsterdam shows there is only a "negligible" chance that the enigmatic apes are a new branch of the primate tree.
Hicks were able to observe the animals for a total of 20 hours.
"I see nothing gorilla about them. The females definitely have a chimp's sex swellings, they pant-hoot and tree-drum, and so on," he told the British science weekly, whose report appears in Saturday's issue.
Samples of a DNA recovered from faeces also put the animals in a recognised subspecies of chimp, Pan troglodytes schweinfurthii.
Even so, the Bili apes are unusual, as they have a gorilla-like crest on their skulls and howl during the full moon.
About 18 kms (11 miles) northwest of Bili, Hicks came across a large community of the animals that apparently had never met a human before.