Oregramma illecebrosa was likely an ancestor to modern butterflies, but had one critical difference.
The scientists believe they may have found one of the oldest known butterfly-like insects on the planet. The species belonged to a long-extinct genus of “lacewing” insects, called Kalligrammatid. Much like many present-day butterfly species, Oregramma illecebrosa had large “eye spot” patterns on its wings, most likely used to deter predators. And like their descendants, lacewings used a long, straw-like tongue to siphon nectar from flowers.
The scientists, who were studying sites more than 165 million years old in northeastern China and eastern Kazakhstan, say that the fossil is a prime example of convergent evolution, when two distant species develop similar traits and behaviors independently of one another. The newly discovered fossils fill in a key gap in scientists’ understanding of the evolution of insects.
“Upon examining these new fossils… we’ve unraveled a surprisingly wide array of physical and ecological similarities between the fossil species and modern butterflies, which shared a common ancestor 320 million years ago,” said David Dilcher, a paleobotanist from Indiana University.
Upon looking at the lacewing fossils under closer scrutiny, Dilcher and his research team noticed traces of food and pollen stuck in the proboscis of the insects, suggesting that during the Triassic and Jurassic periods, they fed on bennettitales. They also boasted hairy legs that likely helped them carry pollen, playing a key role in plant fertilization millions of years ago.
The discovery of Oregramma illecebrosa fossils is a huge leap forward in scientist’ understanding of the evolution of winged insects, and also lends new insights into how plants interacted with insects and evolved alongside them.
The study was published in the journal Proceedings of the Royal Society B. A press release from Indiana University describing the details of the study can be found here.