palaeopterans

Palaeopterans is a broad, informal grouping of ancient insects that possessed wings that were held vertically when at rest, either folded together or held out to the sides. This characteristic is in contrast to the Neoptera, which can fold their wings back over their abdomen. The Palaeoptera are an extinct group, with their last known representatives disappearing during the Permian period.

The palaeopterans are divided into two main orders: the Odonata, which includes modern dragonflies and damselflies, and the Ephemeroptera, which includes modern mayflies. Both of these orders are characterized by the characteristic wing posture of their extinct ancestors. However, it is important to note that modern Odonata and Ephemeroptera are still considered palaeopterans due to their wing articulation, even though they are not extinct.

The Palaeoptera first appeared during the Devonian period, around 400 million years ago, and diversified throughout the Carboniferous and Permian periods. They were a dominant group of insects during the Paleozoic Era, with many large and diverse forms. The extinction of most palaeopteran lineages at the end of the Permian period is thought to be linked to major environmental changes that occurred at that time, including a significant drop in global temperatures and widespread habitat loss.

While the palaeopterans are an extinct group, their legacy lives on in the surviving orders of Odonata and Ephemeroptera. These modern insects are important components of many ecosystems and provide valuable insights into the early evolution of insects and the development of flight. Studying palaeopterans helps us understand the evolutionary pressures and environmental conditions that shaped insect diversity over geological time.