Spatial patterns in the population dynamics of the scallop Psychrochlamys patagonica were analyzed in Uruguayan waters of the southwestern Atlantic Ocean between 35°50′S (northern edge of the species distribution) and 36°50′S. The water depth ranged from 75–135 m. Survey stations were located every 10 miles on parallel transects along the latitudinal gradient. Population structure revealed three modal classes differing in strength between latitudes, indicating recruitment variability. However, the second mode was weak between 35°50′S and 36°10′S, suggesting poor recruitment at the northern end of the scallop's distribution. Relative numbers of recruits decreased with latitude, whereas recruit density was directly related with spawner density, reaching asymptotic values at highest adult densities. Growth curves (size-at-age data) differed between latitudes and a likelihood ratio test indicated that these differences could be explained by the combination of the von Bertalanffy parameters H_∞K. Predicted mean weight for a standard length of 60 mm H followed a nonlinear increase from northern to southern latitudes. Natural mortality (M) decreased with latitude, being more than 3 times higher at 36°00′S (1.77 y⁻¹) than at 36°40′S (0.46 y⁻¹). Projected biomass was zero from 35°50′S to 36°10′S, increasing toward southern latitudes. The clear spatial patterns found seem to be caused by a marked environmental gradient at the northern end of the study area that constrains the geographic range of P. patagonica. Given the sedentary life-history characteristics of P. patagonica, its persistent spatial structure and the marked spatial patterns in its population dynamics, a set of spatially explicit management tools, such as rotation of fishing areas and reproductive refuges, should be used.