A cladistic approach for generic delimitation of Paracloeodes Day, Rivudiva Lugo-Ortiz & McCafferty, and Varipes Lugo-Ortiz & McCafferty (Ephemeroptera: Baetidae)

摘要

The taxonomic knowledge of Baetidae has been greatly improved in the last decades in South America. Despite the advances, there are problems that need to be addressed. One of these problems is doubt concerning the systematics of species assigned to the genera Paraclorodes Day, Rivudiva Lugo-Ortiz & McCafferty, and Varipes Lugo-Ortiz & McCafferty, and the evolution of long setae on femora. In the present paper, the monophyly of these three genera is tested using a cladistic approach. The matrix included 53 species and 151 morphological characters: 127 for nymphs and 24 for adults. The dataset was analyzed under equal and implied weights with nine values of k. Group support was estimated with relative Bremer and frequency differences. The results corroborate (i) the paraphyly of Paracloeodes and Varipes, which become monophyletic without P. caldensis + V. singuil, proposed as a new genus Rhopyscelis gen. n., (ii) the long setae on femora as an independent acquisition between Rhopyscelis gen. n. + Varipes and Rivudiva, (iii) the transversal rows of setae on femora as an independent acquisition between Rhopyscelis gen. n. + Varipes and Rivudiva, (iv) the spine on subgenital plate as an independent acquisition between Paracloeodes, Rivudiva and Gen. A.