Geographic variation, the system and the evolution of gulls of complex Larus argentatus pontoppidan, 1753 – Larus cachinnans pallas, 1811 inhabiting the Russia

On the big collection material – 192 specimens – geographical variability of dimensional and painting signs at adult large white-headed seagulls subgenus Larus, living in the north of Russia from Barents Sea to Anadyr and in the south – from Black Sea to Transbaikalia is investigated. Quantitative methods of an estimation of variability on areas are used and regions where there is a change of tendencies of variability are revealed. In the north of such region it is located from northern coast of the White Sea to the bottom current of the rivers of Pechora and Ob where the small and dark form lives. On Tajmyre explosion of variability of signs is registered that allows to assume a hybrid origin of this population. In territory from Novosibirsk islands to Anadyr inclusive repr esentatives of uniform population live. Southern populations are characterised bigger differentiation of morphological signs and smaller degree of them variability in comparison with the northern. The Larus argentatus – Larus cachinnans complex is not ring species. It is the combinations of the specieses and subspesieses heterogeneous by their different origin. Now in Russia 5 specieses of the L. argentatus – L. cachinnans complex inhabit: Larus argentatus Pontoppidan, 1763, Larus heuglini Bree, 1876 (L. h. heuglini Bree, 1876, L. h. barabensis Johansen, 1960), Larus vegae Palmen, 1887 (L. v. vegae Palmen, 1887, L. v. mongolicus Sushkin, 1925), Larus cachinnans Pallas, 1811 and Larus armenicus Buturlin, 1934.