The Oldest Known Bloodsucker

It's not exactly Jurassic Park's perfectly preserved mosquito in amber, but it's still an incredible find. Researcher have uncovered fossils of blood-suckers dating back to an estimated 130 million years ago, making them the oldest fossils of blood-feeding insects ever found.

The insects, identified as members of the Heteroptera or "True Bug" insect taxon, were discovered within China's Yixian Formation, which has been known to be rich with fossils from the Cretaceous period, which lasted between 145 and 66 million years ago.

Three insect fossils in all were identified as part of the Early (lower) Cretaceous period, about 130 million years ago. All three fossils were found to contain high levels of iron, which indicated that they fed on blood. One insect in particular appears to have been fat with blood just before its remains were preserved, indicating that it had just fed.

Unfortunately, chemical analyses could not determine if these insects fed on dinosaurs, other early animals, or both.

Prior to this discovery, the oldest known specimen of a blood-sucking insects was estimated to be about 100 million years old.

According to the authors of a study published in Current Biology, this latest discovery will push back the record of hematophage (blood-sucker) lineages even further.

"Our understanding of their early evolution is hindered by the scarcity of available material and the difficulty in distinguishing early hematophages from non-blood-feeding relatives," the authors explained.

Such well preserved specimens, looking a lot like large fleas, will help refine the evolutionary record.

Blood sucking among insects is not uncommon. In fact, a review of modern knowledge on hematophages (as of 2012) revealed that blood sucking is an ideal evolutionary route, having separately developed in two known branches of True Bugs alone.

The fossil study was published in Current Biology on July 24.