The last larval instar of Aeshna absoluta Calvert 1952 and A. confusa Rambur 1842, as well as that of the light form of Aeshna variegata Fabricius, are described for the first time and compared with the other Patagonian larvae of this genus. They can be identified based on prementum width/length ratio, number of teeth on each side of the prementum median cleft, shape of prothoracic processes and relative length of the terminalia.