Discovery took a group Boganiidae, and found near it a plant of the Chinese experts have described as ancient cycads: amber after millions of years have kept them in direct contact with the time when the Earth was ruled by dinosaurs and before their death had more than hundreds of millions of years.
This incredible find is all the more valuable considering that boganiid beetles scarcely turn up in fossil records.
Dr Chenyang Cai, a research fellow at the University of Bristol, said: "Boganiid beetles have been ancient pollinators for cycads since the age of cycads and dinosaurs".
When Dr Cai first saw the fossil he was immediately intrigued and recognised its bristly cavities might suggest the beetle was a pollinator of cycads. How old? Likely before the breakup of the Gondwana supercontinent during the Early Jurassic, some 167 million years ago, Cai says. Another evidence of existing insectoid pollinators dates back to about 165 million years.
According to the researchers, the prehistoric plants that the beetles helped fertilize included cycads. This particular beetle fossil was discovered in Burmese amber recovered from the Cretaceous biota found in northern Myanmar's Kachin State.
But before angiosperms, animals like the 160-million-year-old Lichnomesopsyche gloriae, an extinct scorpionfly, used its 10-millimeter-long proboscis as a straw to suck out nectar from gymnosperms (flowerless plants), spreading pollen in the process. This discovery suggests an ancient origin for beetle pollination of cycads long before the rise of flowering plants. But pollen grains are also rare, as they are very tiny and can only be found with the use of powerful microscopes after careful preparation.
After that Liqin Li from the Chinese Academy of Sciences concluded the pollen actually belonged to an ancient cycad.
The finding, along with the current disjunct distribution of related beetle-herbivore and cycad-host pairs in South Africa and Australia, support an ancient origin of beetle pollination of cycads, researchers said. Unlike flowering plants, or angiosperms, gymnosperms had a simple fertilisation strategy.
Today, most flowering plants, including many food crops, could not reproduce without the insect transport of pollen.
Cai notes that the findings together with the distribution of modern boganiid beetles lead him to suspect that similar beetle pollinators of cycads are yet to be found.