Modification of the "acute" method for calculating the final preferred temperatures: As applied to Daphnia longispina (Crustacea: Cladocera)

Given the global temperature anomalies observed in recent years, knowing the temperature preferences of ectotherms is very important. The purpose of this study was to determine the final preferred temperature (FPT) and the preferred temperature (PT) range in non-acclimated animals in comparison with acclimated animals, as well as with data obtained by the gravitational method using the example of Cladocera Daphnia longispina. For the first time, the FPT in D. longispina was determined by the "acute" and gravitational methods (18.4 and 18.8 ± 1.7 °C, respectively). We showed that it is possible to calculate the PT range from the standard deviations and/or confidence intervals of PT linear regression that cross the line of equality. The range of PT for acclimated D. longispina obtained by the "acute" method was 17.5-19.4 °C and 16-22 °C as calculated by the gravitational method. The ranges of pejus (7-15 and 23-24 °C) and avoided (3-6 and 25-27 °C) temperatures were also determined. The possibility of using the "acute" method for determining FPT in animals selected from natural habitats without prior acclimation has been shown.