A new species of insect that looks like a leaf, which was alive approximately 270 million years ago, is described in a study published in Nature Communications this week. The finding extends the fossil record of leaf mimicry by over 100 million years.
Modern katydids are well known for their mimicry of leaves, which enables them to hide from predators in plain sight. However, the oldest evidence of leaf mimicry had come from the Mesozoic Era (around 252 to 66 million years ago), and the katydids (Tettigonioidea) themselves were thought to have originated in the Jurassic (a period within the Mesozoic, dating from around 201 to 145 million years ago).
Romain Garrouste, Andre Nel and colleagues describe the new katydid, Permotettigonia gallica, from a fossil found in south-eastern France and dating from about 270 million years ago, during the middle Permian. Analysis of the new katydid’s forewing shows that it had a leaf-mimicking pattern closely resembling that of modern katydids.
Although the plant fossil record is not complete enough to identify which plant species the Permian katydids were imitating, the findings suggest that these ancient insects faced similar threats from predators as their modern relatives, and that plant mimicry evolved earlier than previously thought.