Revaluation of the prothoracic pleuron of the membracidae (Homoptera): The presence of an epimeron and a subdivided episternum in Stictocephala bisonia Kopp and Yonke, Oxyrhachis taranda (Fabr.), and Centrotus cornutus (L.)

The propleuron of adults of Stictocephala bisonia Kopp and Yonke, Oxyrhachis taranda (Fabr.) and Centrotus cornutus (L.) (Homoptera: Membracidae) and 5th-instar nymphs of S. bisonia is investigated using scanning electron microscopy of the external and internal skeletal surface. Criteria for homologizing propleural features in the Pterygota are detailed in an attempt to resolve contradictions of earlier interpretations. In the species examined, the following features occur in adults and in the nymphs of S. bisonia: the pleural sulcus, pleural apophysis, episternum, epimeron, precoxale, and trochantin. In adults, the episternum is separated into an anterior and a lateral part. The prothoracic tooth of O. taranda is an epimeral feature.