Oldest Known Pollen-carrying Insect Lived About 280 Million Years Ago, Pushing Fossil Records

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Two paleontologists from the Russian Academy of Sciences and one from the University of Silesia in Katowice identified the oldest known pollen-carrying insect in Russia. The Tillyardembiids, or earwig-like insects, were discovered along the riverside near the Russian settlement of Chekarda.

Researchers described the insect fossil in full in their study, titled "The Earliest Pollen-loaded Insects From the Lower Permian of Russia," which was published in the journal Biology Letters.

Crawling Insects Carrying Pollen

Previously, the oldest known pollen-carrying insect was dated to have lived approximately 160 million years ago. But Tillyardembiids fossils dated back to the Permian period about 280 million years ago, Phys.org reports.

The fossils of these ground-dwelling insects were unearthed while researchers were looking through a massive collection of ancient insect fossils kept at the Borissiak Paleontological Institute in Moscow. Researchers said that the earwig-like insects were about 1.5 centimeters long and had flimsy wings, which suggests they most likely spent most of their time on the ground or crawling on plants.

They discovered six of the same insect variety among the 425 petrified animals, each with pollen grains on to their thoraxes, legs, and abdomens. Scientists believe that more of the insects in the collection were pollen transporters, but that the evidence was washed away when the specimens were cleaned for research.

Only two varieties of pollen were found, suggesting that the insects spend the majority of their time on one or two trees or shrubs. Gymnosperms, a type of seed-producing plant without flowers, produced both types.

Pushing Back Fossil Record of Pollinating Insects

The Tillyardembiids was first described in 1937 and preserved in what started out as fine-grained sediments. According to Science News, the discovery pushes back the fossil record of insects transferring pollen from one plant to another, which is an important part of contemporary pollination, by roughly 120 million years.

Paleoentomologist Michael Engel from the University of Kansas in Lawrence who was also not involved in the study said that the pollen-laden insects were quite selective in the tree species they visited after discovering that they just have a few types of pollen stuck on them.

He added that the reason could be that there are probably vast amounts of such specialization that occurred even before Tillyardembia, although there is no evidence of that yet.

The researchers admit that it is impossible to tell if the insects were truly part of the plant pollination process based on the fossil specimens or the pollen adhering to them; if they were not, they were most certainly at least antecedents.

The team's next step is to continue studying the specimens in order to uncover evidence of a pollen-trapping mechanism, which would indicate that pollen-tracking was done on purpose. Scientists also intend to examine the pollen to determine if it has acquired features that allow it to adhere to any passing pollinators.