Sulawesi water rat

The Sulawesi water rat, Waiomys mamasae, also called the Mamasa water rat or Mamasa rat, is a semi-aquatic rodent of the family Muridae and the only species of its genus Waiomys. K. C. Rowe, A. S. Achmadi and Esselstyn described it in 2014 from a specimen taken by hand in a shallow, slow-moving highland stream at about 1571 metres on Mount Gandangdewata near Rantepangko in Mamasa, West Sulawesi, Indonesia, and it is known only from that area. It is a small, densely furred, broad-snouted rat with a grey-brown back, weighing about 64 grams, and it is the only semi-aquatic rat on Sulawesi. The stomach of the one specimen examined held the larvae of black flies and net-spinning caddisflies, which suggests that it dives for food. The Mammal Diversity Database places it in the tribe Rattini of the Australasian realm and gives its Red List status as Not Evaluated.