Abstract
Documenting rare species often relies on a limited number of specimens and, despite posing taxonomic challenges, has become increasingly important in the context of the current biodiversity crisis. This is the case for Thraulodes marianoi Silva, Salles & Pinto, 2020, a mayfly endemic to the Atlantic Forest and originally described from a single male collected in the Mananciais da Serra Protected Area, Pico do Marumbi State Park, state of Paraná, Brazil. Here, we expand the knowledge of this species, one of the least known mayflies in Brazil. The male is redescribed, incorporating previously unreported morphological characters, and the female, eggs, and subimagos of both sexes are described for the first time. With the discovery of the female, sexual dimorphism in coloration was identified: abdominal tergites III–V in females are not white as in males, but instead uniformly brown, while the forewings of subimagos of both sexes lack a dark brown basal half. These new data expand the species diagnosis and reduce gaps in the taxonomic and diversity knowledge of Ephemeroptera from the Atlantic Forest. Among the 32 species of Thraulodes reported from Brazil, this is the only one recorded from the state of Paraná.
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