A revision of Caenodelphax (Hemiptera: Fulgoroidea: Delphacidae) to include species misallocated to the polyphyletic genus Delphacodes

Delphacid planthoppers (Hemiptera: Fulgoroidea: Delphacidae) are of worldwide economic interest due to their propensity to attack crop plants. Despite their importance as crop pests, much of their evolutionary history remains poorly understood; certain genera within Delphacidae are in need of taxonomic revision. The western Palearctic genus Delphacodes Fieber, 1866 once included more than 136 species, but was redescribed with a more limited definition, reducing it to only 10 species. This left the majority of Delphacodes species needing to be reallocated to other genera. Hamilton (2002) hypothesized that 10 Delphacodes species belong in the Nearctic genus Caenodelphax Fennah, 1965, but did not specify the taxa except that he moved C. atridorsum from Delphacodes. Hamilton redescribed Caenodelphax in a broader sense than prior authors; at this time, it consists of only 4 species, all previously assigned to Delphacodes. This project will undertake an investigation of Hamilton’s hypothesis by examining a subset of approximately 17 Delphacodes and Caenodelphax species with reference to morphological and molecular phylogenetic analyses in order to determine their evolutionary relationship, and culminate in the development of online resources for included taxa.