Articles | Volume 20, issue 1
Research article
02 Sep 2016
Research article |  | 02 Sep 2016

Reinvestigation of Protelytron permianum (Insecta; Early Permian; USA) as an example for applying reflectance transformation imaging to insect imprint fossils

Olivier Béthoux, Artémis Llamosi, and Séverine Toussaint

Abstract. We reinvestigated the holotype of Protelytron permianum, one of the earliest putative stem-dermapteran (i.e. stem-earwig). We recurred to reflectance transformation imaging (RTI) to deliver exhaustive and interactive photographic data. We were able to ascertain the occurrence of broadenings located along veins of the hind wing vannus and forming an arc, as well as a series of radiating folds, alternatively concave and convex. Such an organization is diagnostic of Dermaptera, in which it is indicative of hind wing folding mechanisms, particularly elaborated in these insects. We provide a foldable, paper model of the hind wing. Based on the case presented herein we anticipate that RTI process will be a major upheaval in the documentation of fossil insects preserved as imprints.

Short summary
Fossil insects preserved as an imprint on laminae have subtle differences in relief which can be difficult to photograph. Recourse to reflectance transformation imaging allowed us to deliver exhaustive and interactive photographic data for Protelytron permianum. Based on these data we were able ascertain that it is an early relative of earwigs. In order to better appreciate its elaborate hind wing folding mechanism, we provide guidelines to build and operate a paper model.