Based on field surveys in 2013 – 2015 of four local populations of Bombina bombina and Pelophylax ridibundus in spawning lakes in the Medveditsa river valley (Saratov region) it was found that the body length (SVL) and weight of mature females of B. bombina and P. ridibundus ranged from 31.1 to 49.7 mm and from 63.1 to 138.1 mm; from 2.64 to 8.43 g and from 25.4 to 181.0 g, respectively.