Ethiopian Water Rat

Nilopegamys plumbeus is specifically adapted to live near or in close contact with water. There are other rodents adapted to live in wetlands such as marsh rice rat or the European water vole. Out of all other African aquatic rodents however, the Ethiopian amphibious rat has the most extreme adaptations to its environment. They have a pair of adapted "waders" on their feet recognizable as webbing. Since N. plumbeus is so specifically adapted to its environment it makes living elsewhere very difficult. This is why scientists think that with the degradation of its habitat, N. plumbeus is now likely extinct. The rat belongs to the family Muridae and has the largest cranial capacity of any African muroid ever sampled. They also have very large brains compared to their body size and given the average brain size of aquatic rodents.

In late March 1928, the Ethiopian amphibious rat was cataloged for the first time. The specimen was discovered in a trap set by Wilfred H. Osgood, and was unlike any African rat he had seen before. The rat showed multiple adaptations to aquatic life which is uncommon for rats in Africa. Aquatic rats have been observed in South America but never before in east Africa. The Ethiopian amphibious rat has been spotted very few times in the wild. It has been sighted in the Ethiopian highlands in their wetland areas. The single found specimen was located near the Lesser Abay River in central Ethiopia. This rat is listed as critically endangered but many researchers studying the rodent fear it is already extinct due to two failed attempts to locate and track the rat.