It’s not the big ears, sharp teeth, or long legs that inspired the naming of this newly described species, but its long, pink, flat nose: Meet the Hog-nosed rat, Hyorhinomys stuempkei. Discovered on the Indonesian island of Sulawesi in 2013, the furry critter is so different from anything else described that it doesn’t just represent a new species, but a whole new genus. In fact, the scientists behind the discovery seem to be on something of a roll, as this latest find marks the third new genus described by them since 2012.
The animal is classed as a “shrew-rat,” named in part due to those impressive teeth, and is one of 13 known species of this group found scampering round the forests of the Philippines and Sulawesi. In addition to the big teeth, large nose, and long hind legs suspected to be used for hopping, it also apparently has longer than normal urogenital – or pubic to you and me – hairs. All of these weird characteristics, as well as the results of genetic analysis, make it sufficiently different from other known shrew-rats to fall into its own genus. The new species is described in the Journal of Mammalology.
Another of the animal's oddities is the apparent lack of a specific jaw muscle attachment found in most mammals, called the “coronoid process.” This adds an extra connection from the jaw to the skull, allowing animals to chew more powerfully. This indicates that the Hog-nosed rat has a diet that doesn’t require much chewing, and indeed, the researchers found that they feed mainly on earthworms and beetle larvae.
The team of scientists from the Louisiana State University, Museum Victoria in Australia, and Museum Zoologicum Bogoriense in Indonesia have been studying the biodiversity of Sulawesi since 2010 due to its geographical complexity and the fact that it occupies a unique cross roads between Asia and Australasia, with an odd mix of species related to others found on both continents. While they weren’t particularly surprised to find new species in this understudied region, they were surprised to find just how unique they are.
Image in text: Kevin C. Rowe/Museum Victoria