Contribution to the taxonomy of Paracloeodes Day 1955 (Ephemeroptera: Baetidae) from South America.

In recent decades, major advances in the systematics of the Western Hemisphere genus Paracloeodes Day have been made in South America. Despite the taxonomic progress, uncertainties in identification remain due to the morphological similarities among some nymphs and due to the general lack of knowledge of the imago stages (only 4 of 20 are described from throughout the range of the genus). This study addresses these impediments in part through description of the male imagoes of six species (P. atroari Nieto Salles, P. binodulus Lugo-Ortiz McCafferty, P. ibicui Lugo-Ortiz McCafferty, P. pacawara Nieto Salles, P. peri Nieto Salles, P. waimiri Nieto Salles), description of two new species based on morphologically distinct nymphs (P. aristotelesi sp. n. and P. carolinae sp. n.), description of one new species based on morphologically distinct nymph and male imago (P. prismatobranchus sp. n.); redescription of three species based on type material (P. ibicui Lugo-Ortiz McCafferty, P. leptobranchus Lugo-Ortiz McCafferty and P. eurybranchus Lugo-Ortiz McCafferty); proposal of one new synonym based on morphological analyses of specimens from Bolivia, Brazil and Uruguay, including type specimens (P. pacawara = P. morellii Emmerich Nieto); and the presentation of a new key to identify nymphs from South America to the species level.