The Hydrus(Interfector nilus.) is so rare that some think it a bird, a snake or even a Dragon.
They are 1 foot long and 3 to 6 inches high. They are furry when dry but they feed on crocodiles and (infrequently) hippos by rolling in mud, crawling into the mouth of its prey and eating it from the inside. They live along the banks of the Nile.