A mosquito fossil has a 46-million-year-old meal of dried blood in its belly, researchers say.

The rare mosquito fossil has an engorged belly full of ancient blood.

"It is an extremely rare fossil, the only one of its kind in the world," said Dale Greenwalt, lead author of the study. It will be published in the Proceedings of the National Academy of Sciences

The mosquito fossil was found in a Montana riverbed. Scientific instruments detected unmistakable amounts of iron in the abdomen of the mosquito.

Investigators may not be able to discover what creature the blood came from, however-a fossil that old doesn't have extractable blood.

Sadly, real life is not the movie Jurassic Park.

Researchers believe it may have been blood from a bird, as the ancient mosquito fossil found resembles a modern one from the genus Culicidae, which prefers to feed on modern birds.

"But that would be pure speculation," said Greenwalt, who is a retired biochemist and volunteers at the Smithsonian Museum of Natural History in Washington.

The fossil is not the oldest known mosquito fossil-that one is 95 million years old, found trapped in amber in Myanmar. However, it is "a very exciting find," said Lynn Kimsey, an entomologist at the University of California.

"Having an actual blood-engorged female mosquito associated with males in the same fossil formation is hugely unlikely," said Kimsey.

Kimsey was not involved in the research but called it "impressive," explaining

"Here, the authors have been able to use mass spectrometry to elucidate the abdominal contents and thus blood-feeding in a fossil some 40 million years old," she added, describing the research as "impressive."

 The fossil Greenwalt used was in a box in a friend and fellow researcher's basement. Eventually, the box was  donated to the Smithsonian Museum

"As soon as I saw it, I knew it was different," Greenwalt said.

However, this sadly isn't Jurassic Park--which is innacurate anyway, Greenwalt laughed.

Greenwalt pointed out the mosquito pictured in the movie was a male, and male mosquitoes do not feast on blood.

"Like a lot of science fiction, it kind of predicted what we might be looking at in the future," he said.