It sounds like something out of the "Alien" movie series, but wasps that lived during the age of dinosaurs laid eggs inside fly pupae, with the wasps eating the flies from the inside out.
The study, published in the scientific journal Nature, revealed that four new wasp species were found inside fossil pupae that date back to the Paleogene period, approximately 65 million to 23 million years ago. The female wasps would lay their eggs inside the fly pupae and as the wasps grew, they would harvest the flies' bodies as nourishment.
The most common wasp has been named Xenomorphia resurrecta, after the parasitic Xenomorph in the "Alien" movie series. The other species that were found are named Xenomorphia handschini, Coptera anka and Palaeortona quercyensis.
"About 50 [percent] of all animal species are considered parasites," the study's authors wrote in the abstract. "The linkage of species diversity to a parasitic lifestyle is especially evident in the insect order Hymenoptera. However, fossil evidence for host–parasitoid interactions is extremely rare, rendering hypotheses on the evolution of parasitism assumptive."
The study, led by Thomas van de Kamp, noted that "evidence for parasitism in fossils is generally rare, as it requires preserved information of interaction between both partners."
The only previous example of a parasitoid wasp inside its preserved host was found in the Quercy region in France, and is approximately 34–40 million years old, the researchers wrote.
The findings were made possible after van de Kamp and the other researchers looked into the pupae with X-ray scans and then used 3-D modeling to reconstruct what they had seen, according to LiveScience.
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