Protelytrodina

Protelytrodina is an extinct suborder of insects belonging to the order Coleoptera, which comprises beetles. These primitive beetles are known from the fossil record, dating primarily from the Permian period. Their most distinctive feature, and the source of their name, is the presence of elytra, the hardened forewings characteristic of beetles, which are described as "primitive" or "early" in their development compared to later beetle groups.

Fossil specimens of Protelytrodina are typically found in ancient lakebed sediments and other sedimentary rock formations. The morphology of these fossils reveals a beetle-like body plan, including a head, thorax, and abdomen, along with the distinctive forewings. The hindwings, which were used for flight, were likely membranous and folded beneath the elytra when at rest.

The exact phylogenetic position of Protelytrodina within Coleoptera is still a subject of scientific discussion. Some researchers consider them to be an early offshoot of the beetle lineage, representing a transitional form between more ancestral insect groups and modern beetles. Others place them in a more derived position within the order. Their study provides valuable insights into the early evolution of beetles and the development of key insect features like the elytron. The group appears to have gone extinct by the end of the Permian, with no known descendants in younger geological periods.