This study was carried out during the austral summer of 2015 (15 January to 15 February) and assessed freshwater macroinvertebrate diversity associated with lakes and ponds along the altitudinal gradient of the Róbalo river watershed, located in the Magellanic sub-Antarctic ecoregion. The latter has a steep elevational gradient, peaking at around 1000 m a.s.l., and marked changes in temperature and landscape composition can be observed over relatively short distances. Four lagoons were chosen, as they were located on different altitudinal levels, thus allowing for comparison between the different zones found within the gradient. Along with the physical description of each lagoon (temperature, pH and conductivity), the surrounding habitats were characterized. Within each lagoon, four different habitat types were identified based on substrate composition, and the presence/absence and type of vegetation (vascular or non-vascular).