A McGill-led research team has identified a new species of praying mantis thanks to imprints of its fossilized wings.
It lived in Labrador, in the Canadian Subarctic around 100 million years ago, during the time of the dinosaurs, in the Late Cretaceous period.
The researchers believe that the fossils of the new genus and species, Labradormantis guilbaulti, helps to establish evolutionary relationships between previously known species and advances the scientific understanding of the evolution of the most 'primitive' modern praying mantises.
The research team, which included members from the Musée national d'Histoire naturelle in Paris, and the Musée de paléontologie et de l'évolution in Montreal, found the specimens during fieldwork at an abandoned iron mine located in Labrador, near Schefferville, Quebec. The findings were published in the journal Systematic Entomology on January 20.
"Our days were spent essentially scouring the surface of piles of rubble that had been excavated from the mine," said Alexandre Demers-Potvin, a PhD student at McGill, a National Geographic Emerging Explorer, and the lead author on the paper.
"Every now and then, one of the burgundy rocks on the ground would contain either a fossil leaf or a fossil insect, which we would then promptly collect. When the two fossils of Labradormantis guilbaulti were found in the field, none of us could identify them at first. It was only when I showed photos to paleoentomologist Olivier Béthoux, the senior author of this paper, that we started to think that we had the hind-wings of a previously unknown primitive mantis species."
It was already known that most modern praying mantises, with their characteristic grasping forelegs, look very different from their oldest fossil ancestors. However, it has been difficult for paleontologists to trace mantis evolution more precisely because of the multiple gaps in the fossil record of these insects.
By using Reflectance Transformation Imaging (RTI), an emerging photographing method in paleontology, the researchers were able to get a better view of the intricate network of veins lying along the fossil wings.
They noticed a vein lying along the hind-wing's folding line (called AA2*) that is only found in one modern mantis lineage, the Chaeteessidae family. Following this key observation, they produced a revised evolutionary tree that included Labradormantis among some of its living and extinct relatives.