I perform a taxonomic study for C. puerilis. From the description of male and female adults, and redescription of the nymph, six adult and eleven immature traits were identified in opposition to the remaining species of Chilenoperla. With these results, I propose a new genus, Ericiataperla, at which I have assigned the species in question under a new combination. The case study shows the importance of correctly associate the developmental stages in aquatic insects to assign ecological attributes and estimate the diversity of the taxa involved.