Ovipositor and mandible structure of a new fossil insect species reveals a novel role for orthopterans in Carboniferous forests

The discovery of a new species of fossil insect, Ctenoptilus frequens, reveals the place of Orthoptera (grasshoppers, crickets, locusts, and crickets) in Carboniferous forests. The study is published in eLife.

Fossil insects from about 300 million years ago are difficult to relate to current insect groups. Ctenoptilus frequens, which belongs to the lobeattid group, a group that was as diverse as it was abundant at that time and that is recognized by the veins on its wings, has been associated with various orders that are not very diverse today, such as the Orthoptera.

The analysis of an exceptional sample from the Xiaheyan deposit (China) has made it possible to study the structure of the abdomen of a new species of lobeattid insect: Ctenoptilus frequens. The insect had characteristics similar to those of Orthoptera. Indeed, it had an ovipositor (abdominal appendage used to deposit eggs) composed of three pairs of sword-shaped valves and two systems of articulation of these valves.

The exceptional preservation of the specimens also allowed us to determine the diet of the species based on the shape of its mandibles, compared to that of present-day insects.

This new species was omnivorous, which is consistent with the rarity of attacks found on the foliage of Carboniferous forests and the abundance of lobeattids at that time.

Finally, this study demonstrates the great difference in diversity of ancient insect faunas compared to the present day fauna, the latter being dominated by “metamorphosing” insects (such as flies, wasps and beetles).

 

  • Bibliography: Chen, L., Gu, J.-j., Yang, Q., Ren, D., Blanke, A. & Béthoux, O. 2021. Ovipositor and mouthparts in a fossil insect support a novel ecological role for early orthopterans in 300 million years old forests. eLife. DOI : https://doi.org/10.7554/eLife.71006

Published on: 15/12/2021 12:30 - Updated on: 09/03/2023 17:35