 Despite thorough reviews of the relationships between early Mosasauroidea and redescriptions of the two normally recognized aigialosaurid genera, "Aigialosaurus" and "Opetiosaurus", the status of the family remains uncertain.Dutchak & Caldwell (2009) designated "Opetiosaurus" as a junior synonym of "Aigialosaurus" (as "Aigialosaurus bucchichi"), which suggested a very close relationship between the two.Their own analysis does not strictly support such a conclusion, and neither do subsequent analyses.