Discover special ancient creatures

Chinese scientists have discovered the fossil of the flea Saurophthyrus exquisitus, believed to be a transition between ancient and modern fleas.

In 2012, Chungkun Shih, emeritus professor at Capital Normal University, Beijing, and his colleagues discovered the oldest flea known. This flea has a scientific name, Pseudopulicidae . It lived 165 million years ago, in northeastern China.

This newly discovered flea species has the scientific name of Saurophthyrus exquisitus . They are described as having smaller mouths and bodies than the ancient fleas, but larger than the current fleas.

This species draws blood on the bodies of flying lizards, living about 125 million years ago.

Fossils of the flea Saurophthyrus exquisitus.

Newly discovered fleas are about 1cm long, smaller than the 2cm longest Pseudopulicidae, but 5 times more modern fleas. A part of the genitalia of this species is hidden, with a small blood suction tube. It also has no teeth like the Pseudopulicidae. The Saurophthyrus exquisitus species has longer legs, the hair on the body is shorter and harder.

Researchers believe that this species evolved to match the thick-skinned dinosaur, the host it lives on. The hard hairs used to grip the host's body hair, long legs and genital organs hidden in it can help them jump further.

Scientists believe that this could be a species of transfer between ancient and modern fleas, and it could evolve with the evolution of the host in a way that balances the ability to suck blood and hide.