Identification of the taxonomic status of Scinax nebulosus and Scinax constrictus (Scinaxinae, Anura) based on molecular markers.

The validation of many anuran species is based on a strictly descriptive, morphological analysis of a small number of specimens with a limited geographic distribution. The Scinax Wagler, 1830 genus is a controversial group with many doubtful taxa and taxonomic uncertainties, due a high number of cryptic species. One example is the pair of species Scinax constrictus and Scinax nebulosus, which share a similar morphology. Scinax constrictus is restricted to the Brazilian Cerrado savanna, while S. nebulosus is widely distributed throughout northern South America. Despite the validation of many anuran species, discriminations based only on morphological traits is quite difficult due to the high conservative morphology of some groups. In this context, the present study uses mitochondrial and nuclear genes to provide a more consistent diagnosis and test the validity of S. constrictus as a distinct species from S. nebulosus, as well as evaluate the position of these taxa within the Scinax genus. The topologies obtained herein uphold the monophyletic status of Scinax based on all molecular markers assessed in this study, in all analytical approaches, with high levels of statistical support.