A team of scientists working in a Kenyan rainforest has discovered what is thought to be a new species of elephant shrew. Weighing in at a hefty 600g, the two-foot long creature is unusually large compared to other species.

The mammal, which is more closely related to elephants than to shrews, was caught on motion sensor cameras set up by the Zoological Society of London's Edge of Existence programme in the threatened Boni-Dodori rainforest, which sits on Kenya's north-eastern coast next to Somalia.

"It's really rare to discover a new species of mammal, and it's particularly remarkable that we've found a new species of elephant shrew just five years after the last one was discovered in Tanzania's Udzungwa mountains," says Raj Amin, who led the team. This brings the total number of elephant shrew (Macroscelidea) known to science to 18 species - all found in Africa.

The crew are yet to see one of the species alive, having caught one on camera and found a dead elephant shrew in one of their nets. Members of the Boni tribe also brought them two more dead specimens of the new species.

DNA from the samples is currently being analysed to confirm that the animal is a new species, but Amin remains confident: "You can distinguish elephant shrews based on their colour, and this one looks completely different from all the others."

"It doesn't have a golden rump, or a rufous-coloured face, or spots, but it does have grizzled yellow-brown sides and shoulders, a black rump and thighs and what appears to be a dark mane," says Amin. Because the animal was captured on camera during the day, it is also likely to be diurnal.

Until 2005, security was too tight for scientists to enter the Boni-Dodori forest but in 2008, Amin's team got permission to survey the area. They were amazed at how intact it was, as neighbouring regions have largely been logged and converted into biofuel farms.

"As it turns out, the Boni-Dodori forest is infested with sleeping sickness, a parasite transmitted by the tsetse fly, so herders and other people have left it well alone for the most part," says Amin.

After the inevitable buzz around finding a new species dies down, Amin hopes that the discovery will draw attention to the plight of the roughly 2,216 sq km patch of forest, which may not be protected by sleeping sickness for much longer.

"China wants to rebuild a nearby port in order to ship out minerals, and there are also plans for an oil pipeline," says Amin. "In addition, biofuel companies are growing crops on freshly deforested land that's less degraded, just to make a quick profit."

In January, WWF set up the first conservation project in the forest. The project will last for three years and produce an inventory of the forest's biodiversity.