This furry little critter is kind of unusual — it’s been extinct for 11 million years.
This is kind of like the Coelacanth, a fish which was “extinct” for about 70 million years... until live ones turned up in various fish markets (South Africa, Indonesia, South America). Reading between the lines of this Wikipedia article...
They are the only living species known to have a functional intracranial joint, which almost completely separates the front and back halves of the skull internally. Flexure at this joint may aid in the consumption of large prey. Coelacanths are also mucilaginous; their scales release mucus and their bodies continually exude oil. This oil is a laxative, and makes the fish almost inedible unless dried and salted. Their scales are very rough, and are used by the villagers of the Comoros as sandpaper.
Coelacanth eyes are very sensitive, and have a tapetum lucidum. Coelacanths are almost never caught in the daytime or on nights with full moons, due to the sensitivity of their eyes.
...kind of explains why Ceolacaths were seldom seen (rarely caught) and not popular (difficult to make edible). In real life, they’re a large fish (up to 80kg) and have the occasional bright, shiny scale to show.
And... who pays attention to a rat? Other than a cat, which would not precisely busy itself with anthropological paperwork “post facto”.
Kha-nyou (the rattish critter) was picked up near the village of Doy, close to the Thai border, — and, no doubt and amongst other things, waddles like a duck when it walks.