In March, 1969, a 35-ton carcass was found washed up on the beach of Tecoluta, Mexico. The creature had a "serpent-like body," which was covered in "hard jointed armor," and had a 10-foot bone tusk protruding from its head that was estimated to weigh one ton. Biologists examined the carcass, and though they thought it could be a narwhal, "could not match it with any sea creature known to man."
On April 20, 1969, a seven-man team of scientists reported that the monster was actually a finback whale. Finback whales are the second largest mammals on Earth, only behind the blue whale. But the scientists' explanation did not explain the giant horn on the animal's head.
The Tecoluta mayor allowed the carcass to remain on the beach as a tourist attraction despite the horrible stench that emanated from it.
The monster was never identified, though it may have been some kind of cetacean. Bones of it are on display at the Marine Museum in Tecoluta.
This post is excerpted from my future book Global Globsters, in which I examine discoveries of "sea monster" carcasses from around the world...