Description of the final stadium larva of Erythrodiplax media (Odonata: Libellulidae) with preliminary key to known South American larvae in the genus

The larvaof Erythrodiplaxmedia is described and illustrated based on two exuviae of reared larvaeand one final stadium larvacollected in Xangri-la, State of Rio Grande do Sul, Brazil. The larvaof E. media can be distinguished from other species of Erythrodiplaxby the presence of lateral spines on S8 and S9, the number of premental setae(n = 22), palpal setae(n = 7) and by the mandibular formula. We also provide a preliminary key to known South American larvaein the genus.