Phylogeny of the planthopper genus (Hemiptera, Delphacidae), with the description of two new species from South America.

is a genus of Delphacidae widely distributed and mostly associated with plants in freshwater environments. Despite various taxonomic revisions and thorough research, the delimitation of the genus, its diversity, and its evolutionary history need to be further explored. Moreover, features originally considered distinctive of the genus exhibit variation and should be reassessed. Here, the genus in South America was examined, describing two new species, Remes Lenicov & Mariani, and Mariani & Remes Lenicov, , and providing information on their host plants and geographical distribution. The distribution and host range knowledge of and are also expanded, the male brachypter of described for the first time, and a key to distinguish the species, based on male and female genitalia and their external morphology, is provided. Moreover, the first phylogenetic analysis of the genus is presented, based on the mitochondrial COI gene to clarify the interspecific relationships among its members. Our combined findings support the monophyly of the genus and refine diagnostic features, including the importance of the pygofer's lobed appearance. This comprehensive revision highlights the need for further multidisciplinary approaches to fully understand the evolutionary history of and its interactions with host plants and environments.