Pacific calico scallop can be found in the East Pacific distributing from California, USA to Piura, Peru (Félix-Pico 2006)(Palomares and Pauly 2019). Information about the stock structure could not be found, an assessment unit in the Baja California Sur state, Mexico is here considered, where one of the most important Mexican fishery takes place, in Bahía Magdalena (DOF 2018).