Insects were the first animals to evolve powered flight and did so perhaps 90 million years before the first flight among vertebrates. However, the earliest fossil record of flying insect lineages (Pterygota) is poor, with scant indirect evidence from the Devonian and a nearly complete dearth of material from the Early Carboniferous. By the Late Carboniferous a diversity of flying lineages is known, mostly from isolated wings but without true insights into the paleoethology of these taxa. Here, we report evidence of a full-body impression of a flying insect from the Late Carboniferous Wamsutta Formation of Massachusetts, representing the oldest trace fossil of Pterygota. Through ethological and morphological analysis, the trace fossil provides evidence that its maker was a flying insect and probably was representative of a stem-group lineage of mayflies. The nature of this current full-body impression somewhat blurs distinctions between the ystematics of traces and trace makers, thus adding to the debate surrounding ichnotaxonomy for traces with well-associated trace makers. Of the Ephemeroptera body fossil record is comprised of wings; therefore the trace fossil provides previously unrecorded information about the body plan of the earliest mayflies and their relatives. More significantly, this material somewhat blurs the usual distinctions between trace and body fossils and the traditional dichotomy between paleoichnological and paleontological systematics and taxonomy.