According to the most recently published articles and reviews, 17 extant species belonging to the family Philinidae J.E. Gray, 1850 (1815) sensu lato occur in the Mediterranean Sea. Among them, Philine striatula Monterosato, 1874 ex Jeffreys ms. is presumably the least known Mediterranean taxon and has a long history of published misidentifications until the present day. Based on the type material and recently collected samples from the eastern Atlantic and the Mediterranean Sea, we hereby redescribe its shell morphology and provide further data on its distribution. Within this framework, Philine calva van der Linden, 1995 is confirmed as a junior synonym of P. striatula, and Philine condensa van der Linden, 1995 is regarded as a distinct species. Furthermore, Philine zangherii Coen, 1948 is considered a junior synonym of Philine quadripartita Ascanius, 1772. Literature review also revealed that Mediterranean published occurrences of Philine finmarchica M. Sars, 1859 and Philine lima (T. Brown, 1827) were only based on misidentifications and unconfirmed records, several of which should be ascribed to P. striatula, and that Mediterranean occurrences of Philine condensa van der Linden, 1995 and Philine ventricosa (Jeffreys, 1865) are to be questioned, as more information is necessary to better evaluate their possible presence in the area. Despite limitations of morphological taxonomy and the need of a combined morphological-molecular approach to characterize Mediterranean morphospecies, the present paper lays basis on confirmed/unconfirmed occurrences of Philine taxa in the Mediterranean, and first describes intraspecific variability of a rare and problematic species.