Two new species and new records of Campsurus Eaton (Ephemeroptera: Polymitarcyidae) in Amazon

Campsurus Eaton is the second most speciose genus of mayflies in South America and, until recently, one of the most problematic. The scenario was so disorganized that the description of new species was strongly discouraged. In 2010 the genus started to be revised and, after more than ten years of advances, the taxonomic impediment was drastically reduced, facilitating new researches. The new evidence allowed us to investigate specimens of this genus collected from Amap and Mato Grosso States, Brazil, which were impossible to assign to any species in the past. As results, two new species are described, Campsurus fortuitus sp. nov. and Campsurus froehlichi sp. nov.; and new records are provided for Campsurus cuyuniensis Traver, Campsurus indivisus Ulmer, Campsurus inusitatus Molineri Salles, Campsurus jorgenseni Esben-Petersen, Campsurus litaninensis Spieth, Campsurus nessimiani Molineri Salles, Campsurus pereirae Molineri Salles and, Campsurus segnis Needham Murphy.