A new species of rat has been discovered
A new species of rat has been discovered living in a remote rainforest on the Indonesian island of Sulawesi. The newly found rat has a unique characteristic – no back teeth! This makes it the only rodent in the world with this trait and represents a new step in rodent evolution.
The shrew-like animal, Paucidentomys vermidax, has fang-like upper incisors which are useless for gnawing and no back teeth living exclusively on earthworms. It shares some characteristics with insectivorous shrew rats from the Philippines but has taken an evolutionary step further by doing away with chewing molars completely.
A member of the discovery team, Dr Kevin Rowe from Museum Victoria in Australia, said: "There are more than 2,200 rodent species in the world and until this discovery all had molars in the back of their mouth and incisors at the front. This is an example of how species, when faced with a new ecological opportunity, in this case an abundance of earthworms, can evolve the loss of traits that were wildly successful in previous circumstances."
The creature is described as having a rat-like tail but a long, thin nose, similar to a shrew's. Its only teeth are incisors, which in the upper jaw end in twin points. The Latin derived genus name Paucidentomys means "few-toothed mouse" and the species name vermidax means "devourer of worms".
Dr Rowe said the find was a reminder that wild habitats can still harbour undiscovered species.
The BSAVA has opened submissions for the BSAVA Clinical Research Abstracts 2026.
