Saurophthirus

Saurophthirus is an extinct genus of flea that represents a transition between primitive stem fleas, and modern species. The type species, S. longipes is found in early Cretaceous strata of Baissa, Siberia. The second species, S. exquisitus, is from the [1] is from the Lower Cretaceous Yixian Formation.

Description
Average length of specimens are 2.50 cm (1 in) long and is hypothesized to have sucked the blood of pterosaurs in the Cretaceous, in the way that bat fleas feed on bat blood today.

In popular culture
Saurophthirus is featured briefly in Walking with Dinosaurs, being shown parasitizing an Ornithocheirus.