<p>The hypothesis was tested in order to ascertain whether there is a correlation between geographical and habitat estimates of the optimum for macrophyte species in conditions of a temperature gradient. The influence of asymmetrical response patterns across the environmental gradient on the outcomes of phytoindication was also examined. The study was conducted during the summer of 2023 in the waters of the Dnipro-Orilskyi Nature Reserve, located in the Dnipro region of Ukraine. The temperature optimum of the species was measured during the warmest period of the year and compared with the results of phytoindication and the methods of Ellenberg and Didukh, as well as with estimates of the ecological optimum of species based on habitat data. The study demonstrated a correlation between geographical and habitat-based estimates of the optimum for macrophyte species under temperature gradient conditions. The study sought to determine the correlation between these estimates and those based on point and habitat scales of indicators. The results indicate a significant decline in the abundance of many species under extreme conditions caused by temperature increase. The Didukh scale, after applying the ideal indicator method, demonstrates a high level of accuracy for temperature estimation. The ideal indicator method, which considers the asymmetric distribution of species responses, has shown a high ability to indicate the temperature regime of water bodies in the Dnipro floodplain.</p>