Chinese scientists have discovered fossils of remarkable giant flea-like animals that lived millions years ago in what is now China.
An artist’s impression of Pseudopulex jurassicus (Wang Cheng / Oregon State University)
These ancient creatures, described in the journal Current Biology, were probably 10 times the size of a flea you might find crawling on the family dog – with an extra-painful bite to match.
“These were insects much larger than modern fleas and from the size of their proboscis we can tell they would have been mean,” said George Poinar, Jr., a professor emeritus of zoology at Oregon State University, who wrote a commentary on the discovery in the same issue of the journal.
“You wouldn’t talk much about the good old days if you got bit by this insect,” Prof. Poinar explained. “It would have felt about like a hypodermic needle going in – a flea shot, if not a flu shot. We can be thankful our modern fleas are not nearly this big.”
“It’s possible that the soft-bodied, flea-like insects found in these fossils from Inner Mongolia are the evolutionary ancestors of modern fleas, but most likely they belong to a separate and now extinct lineage,” the researcher added.
The newly discovered species, called Pseudopulex jurassicus and Pseudopulex magnus, had bodies that were more flat, like a bedbug or tick, and long claws that could reach over scales on the skin of dinosaurs so they could hold onto them tightly while sucking blood. Modern fleas are more laterally compressed and have shorter antennae, and are able to move quickly through the fur or feathers of their victims.
“These are really well-preserved fossils that give us another glimpse of life into the really distant past, the Cretaceous and Jurassic,” said Prof. Poinar, who has also studied “younger” fleas from 40-50 million years ago preserved in amber.
“All true fleas are adapted to feeding on warm-blooded vertebrates,” Prof. Poinar explained. “And today 94 percent of the 2,300 known species attack mammals, while the remainder feed on birds. But the unusual characteristics and abilities of the flea-like animals found in these fossils lead scientists to believe their prey were some of the biggest kids on the block – dinosaurs in which they could have fed on the softer skin between scales.”
