A systematic analysis of primary and secondary occurrence data, including new records of the endemic megalopteran Corydalus diasi Navás, 1915 revealed this species is restricted to eastern South America up to Paraguay River and Brazilian Central Plateau (western boundaries), encompassing three biomes: Caatinga, Brazilian savannah (Cerrado) and Atlantic Forest. The known distribution of C. diasi in Brazil was extended by the inclusion of new records for the Araripe Plateau in Southern Ceará, representing a rediscovery of this species for this region since its formal description about 100 years ago. Novel records were also confirmed for the state of Espírito Santo in Southeastern Brazil and the province of Concepción in Paraguay. Therefore, the distribution limits seem to be associated with the presence of large rivers such as Paraguay and Tocantins-Araguaia along the Eastern Amazon forest and southwards to Paraguay. As for the Caatinga, the occurrence of C. diasi is limited to enclaves of Atlantic Forest remnants and high-altitude wetlands, evidencing a direct relationship between the availability of water resources and reproductive events.
Martins et al. (Fri,) studied this question.