In this study has document a new locality and thus a southern extension of the distribution of the lungfish Lepidosiren paradoxa to the coast of the Entre Rios Province in the lower Paraná River. This finding increases the range of L. paradoxa by approximately 500 km and represents the third southern record of this species on the south of South America. Additionally, as this region has been relatively well sampled both during past decades and currently, I discuss possible reasons why this range extension has been observed only recently.