We used the Schumacher-Eschmeyer method for closed populations to estimate and compare the population size of adults of Aeglapaulensis, from Jaraguá State Park (São Paulo, Brazil), in two periods of the year with contrasting climatic conditions (late winter and late summer). The calculated density of adult individuals was considerably higher in the summer (11.5 ind m-2) than in the winter (6.7 ind m-2). This density difference of adult individuals was attributed to variation in the population structure of coexisting cohorts of adults at each sampling season of the year, due to dissimilarities in the cumulative abundance of recruits that effectively become adults after puberty molt, and difference in longevity between sexes.