<i>Liolaemus kingi</i> (Bell) from the eastern and central lowlands and tablelands of Argentine Patagonia, <i>L. archeforus archeforus</i> Donoso-Barros and Cei from the Lake Buenos Aires area, and <i>L. archeforus sarmientoi</i> Donoso-Barros from southern Santa Cruz province and neighboring Chilean territories, form a natural group, which is analyzed here. Serological relationships of the complex and the geographical distribution of its members are discussed.Material digitalizado en SEDICI gracias a la colaboración del Dr. Jorge Williams (FCNM-UNLP).Facultad de Ciencias Naturales y Museo