 Several other subspecies have been named , but are generally no longer considered valid . Most are intergrades that occur where the ranges of various subspecies meet . These include : S. v. ruthenus Menzbier , 1891 and S. v. jitkowi Buturlin , 1904 , which are intergrades between vulgaris and poltaratskyi from western Russia ; S. v. graecus Tschusi , 1905 and S. v. balcanicus Buturlin and Harms , 1909 , intergrades between vulgaris and tauricus from the southern Balkans to central Ukraine and throughout Greece to the Bosporus ; and S. v. heinrichi Stresemann , 1928 , an intergrade between caucasicus and nobilior in northern Iran . S. v. persepolis Ticehurst , 1928 from southern Iran 's ( Fars Province ) is very similar to S. v. vulgaris , and it is not clear whether it is a distinct resident population or simply migrants from southeastern Europe . 
 Several other subspecies <a href='been_done' title='1'><mark>have</mark></a> been named , but are generally no longer considered valid . Most <a href='drop_aux' title='2'><mark>are</mark></a>intergrades <a href='null_relcl' title='3'><mark>that</mark></a>occur where the ranges of various subspecies meet . These include : S. v. ruthenus Menzbier , 1891 and S. v. jitkowi Buturlin , 1904 , which <a href='drop_aux' title='4'><mark>are</mark></a>intergrades between vulgaris and poltaratskyi from western Russia ; S. v. graecus Tschusi , 1905 and S. v. balcanicus Buturlin and Harms , 1909 , intergrades between vulgaris and tauricus from the southern Balkans to central Ukraine and throughout Greece to the Bosporus ; and S. v. heinrichi Stresemann , 1928 , an intergrade between caucasicus and nobilior in northern Iran . S. v. persepolis Ticehurst , 1928 from southern Iran <a href='null_genetive' title='5'><mark>'s</mark></a>( Fars Province ) <a href='drop_aux' title='6'><mark>is</mark></a>very similar to S. v. vulgaris , and it <a href='negative_concord' title='7'><mark>is</mark></a> <a href='negative_concord' title='8'><mark>not</mark></a>clear whether it is a distinct resident population or simply migrants from southeastern Europe . 
Several other subspecies done been named , but are generally no longer considered valid . Most intergrades occur where the ranges of various subspecies meet . These include : S. v. ruthenus Menzbier , 1891 and S. v. jitkowi Buturlin , 1904 , which intergrades between vulgaris and poltaratskyi from western Russia ; S. v. graecus Tschusi , 1905 and S. v. balcanicus Buturlin and Harms , 1909 , intergrades between vulgaris and tauricus from the southern Balkans to central Ukraine and throughout Greece to da Bosporus ; and S. v. heinrichi Stresemann , 1928 , an intergrade between caucasicus and nobilior in northern Iran . S. v. persepolis Ticehurst , 1928 from southern Iran  ( Fars Province ) very similar to S. v. vulgaris , and it ain't clear whether it is a distinct resident population or simply migrants from southeastern Europe .