Variability of body weight (Eremias arguta deserti Gmelin, 1789) and (Phrynocephalus guttatus guttatus Gmelin, 1789) in the southeastern part of the Lower Volga region

One of the aspects of studies of micropopulations of ( Eremias arguta deserti Gmelin, 1789) and ( Phrynocephalus guttatus guttatus Gmelin, 1789) in the conditions of the southeastern part of the Lower Volga region was the observation of inter-seasonal fluctuations in body weight of individuals. Males of Eremias arguta deserti are consistently heavier in the spring than females. In the autumn periods, the results turned out to be contradictory and do not make it possible to conclude which individuals of which sex have the greatest mass. Statistical processing of materials using the Kruskal - Walli’s criterion (H) did not reveal significant differences in Eremias arguta deserti when comparing the mass of all females and males both for all periods and separately in spring and autumn periods. Phrynocephalus g. guttatus also showed no statistical significance when comparing all males and females for the entire period. However, the results obtained when comparing between females and males during the 2018 season, as well as when comparing females of different years, were statistically significant. In addition, the body weight of fingerlings of both groups, between the autumn seasons of 2017 and 2018, revealed statistical significance. Individuals of both Phrynocephalus g. guttatus and Eremias arguta deserti steadily gain body weight, despite the slowdown or complete stop of the growth of individuals in the former and autotomy in the latter. Regeneration of the tail or its absence obviously affects the growth of the trunk of Eremias arguta deserti.