The Indonesian island of Sulawesi boasts a dramatic topography and a rich ecosystem of wildlife that’s often not found anywhere else.
For the past four years, an international team of scientists has been conducting field trips to the spectacular Mount Gandang Dewata, located in Sulawesi’s west. One of the researchers is Museum Victoria’s senior curator of mammals, Dr Kevin Rowe.
"There's an amazing forest in this location," Rowe told SBS Science. "This mountain - Mount Gandang Dewata - is the largest area of intact rainforest on Sulawesi. There are other areas as well, but none are as big; there's just a lot of species found there that are nowhere else."
The latest addition to this list of unique species is the slender rat, Gracilimus radix. It’s a little carnivorous rodent that spends its life foraging in the roots of trees. Genetically it is close to the Sulawesi water rat, Waiomys mamasae - a species the same team described just two years ago.
“This rat is quite different from any others, so we knew immediately in the field that we had something new - but we didn't know what its relatives were,” explains Rowe. “That's why we do a combination of genetics and morphology work on the specimens."
There’s nothing particularly outlandish about the slender rat; it has a small, elongated body and rounded face, and looks quite similar to what a young rat looks like. Still, its anatomy is so unique that it’s not just a new species - the slender rat comprises a whole new genus.
Rowe explains that the rats living on Sulawesi came from Asia over the span of millions of years, and based on where they settled they'd end up becoming different from their relatives over relatively short evolutionary timespans.
It’s the third new genus and fourth new species that’s been discovered on Mount Gandang Dewata in the past four years by the international team that includes Indonesian, Australian and US researchers.
"The degree to which we've found new species on Sulawesi really is amazing," says Rowe. The scientists are grateful for the help of the local people from the village of Rantepangko, who helped guide the researchers far into the reaches of the jungle.
Even though Sulawesi has six national parks and numerous reserves, many of these areas are threatened by increasing deforestation, and Mount Gandang Dewata has no formal protection at the moment, relying entirely on the efforts of the local population to stave off environmental threats.
Researchers are now working on tagging other wildlife in the area as well, with the hope that they'll be able to highlight the need for conservation.
Rowe’s Indonesian colleague Anang Achmadi, from Museum Zoologicum Bogoriense, is currently working on a biodiversity report for the area - the goal is to submit it to the Indonesian Departments of Forestry, National Parks and Research making the case for conservation of the area.
“Mount Gandang Dewata has exceptional conservation value for Sulawesi and Indonesia,” says Achmadi. “Through our discoveries and our ongoing surveys we hope to convince our government that it is worthy of protection.”
Update: The paper describing the new rat is online now, set to appear in the next print issue of the Journal of Mammalogy.