Ahuizotl

“The Ahuizotl is an aquatic monster, originated from Aztec Mythology. They believed that Ahuizotl was a guardian of the lakes, and that his duty was to prevent fishing, being hostile and attacking all who entered his territory.
Some versions of the legend claim that the monster would have the size of a dog, but many descriptions of the strange creature show it as a very large monster.
It‘s described as a creature similar to a dog or coyote, with hands and tail similar with a monkey. At the end of his tail is another hand, which he usually uses to grab his victims when he emerges from the lakes.
An Ahuizotl victim is easily recognized because his body returns to the surface exactly three days after being grabbed to the lake bottom without the eyes, teeth and nails that would be devoured by the monster, who seems to like the crispy parts of the human body.”