Despite the importance of Perisphinctidae ammonite family as a tool (or biogeographic correlation and biostratigraphy during the Oxfordian, these studies are frequently hampered by the intraspecific morphological and geographical variability, and the traditionally used tipologist species concept. A modern systematics, based on a biological species concept (biospecies) taking into account all types of intraspecific variability is likely to provide a more reliable phyllogenetic-biostratigraphic frame, leading as well to a better comprehension of the biogeographic dynamics of the group. The studied recorded successions in the Middle Oxfordian of Rida (NE Iberian Chain, Spain) known by their abundance and by the completeness of the ammonite record, supply a good evidence for the analysis of intraspecific variability and biospecies concept