Wing venation morphology and variability of Gerarus fischeri (Brongniart, 1885) sensu Burnham (Panorthoptera; Upper Carboniferous, Commentry, France), with inferences on flight performance

The Geraridae is a family with no consensual assignment. In order to improve this situation, a revision of the wing venation of Gerarus fischeri (Brongniart, 1885) sensu Burnham (1983) is presented. Gerarus bruesi Meunier, 1909, Archaeacridites elegantissima Meunier, 1909 and Sthenaropoda minor Handlirsch, 1919 are considered as new junior synonyms of G. fischeri. A new interpretation of the hind wing venation is proposed, yielding additional support for the 'panorthopterid' assignment. The wing venation of this species shows outstandingly high variability. For a better resolution of relationships of Geraridae within Panorthoptera, additional studies of representatives of the latter taxon are required.