Genus Pecopteris is a classification of ferns that existed during the Carboniferous period. There are several synonyms that have been used to refer to this genus, including Neuropteris, Odontopteris, and Alethopteris. These names reflect the changes and updates made to the taxonomy of ferns over time. Neuropteris was originally used to describe fossil leaves that were later found to belong to Pecopteris. Odontopteris was another name used for this genus because of its toothed edges, while Alethopteris referred to a broad group of fossil plants that were eventually narrowed down to Pecopteris. The use of these synonyms demonstrates the ongoing process of scientific discovery and refinement in botany.