A strange ‘mermaid’ that appears to be part fish, part monkey and part reptile is being used by scientists in a bid to unravel its mysteries.

The mummy was brought from Japan by an American sailor and donated to the Clark County Historical Society in Springfield, Ohio, in 1906.

With a grimacing face, strange teeth, oversized claws, fish-shaped lower half, and a soft coat of gray hair, he’s been giving museum visitors chills for decades.

But now her secrets could be revealed, after the so-called mermaid underwent X-rays and CT scans for the first time in an effort to decipher her true nature.

Joseph Cress, a radiologist at Northern Kentucky University, said: “Externally it looks like a hodgepodge of at least three different species.

A strange ‘mermaid’ that appears to be part fish, part monkey and part reptile is being released by scientists in a bid to unravel its mysteries.

“There is the head and torso of a monkey, the hands look like those of an amphibian, almost like an alligator, a crocodile or some kind of lizard.”

“And then there’s that fish tail, again, unknown species.”

He added: “It’s originally designed, almost like a Frankenstein, so I want to know what parts came together.”

Natalie Fritz of the Clark County Historical Society said the oddity was a ‘Fiji mermaid,’ a deceptive creature popularized by PT Barnum.

Barnum, whose life inspired the 2017 film The Greatest Showman, displayed a similar display in his American Museum in New York before it collapsed in 1865.

In Japan itself, some legends say that mermaids grant immortality to whoever tastes their flesh.

In a temple in Asakuchi, a Fijian mermaid was worshiped, although it was later discovered that it was made of cloth, paper and cotton, decorated with fish scales and animal hair.

In the United States, however, these mermaids were curiosities.

“Fijian mermaids were part of collections and exhibits in the late 19th century,” Fritz said.