Mediterranean spreading of the bicolor purse oyster, Isognomon bicolor, and the chicken trigger, Malleus sp., vs. the Lessepsian prejudice

The introduction rate of alien species in the Mediterranean Sea is rapidly growing, and their taxonomical identification increasingly challenging. This uncertain often leads to an incorrect estimation number species, route introduction, potential negative effects. particularly true for some bivalves, which are characterized by high variation shells, resulting morphological identification. case two i.e., Isognomonidae a Malleidae both confused historical colonization records Sea, misidentifications, controversial changing nomenclatures that have insofar negatively affected our knowledge on geographical distributions. In this respect, molecular approaches provide strategy especially useful when traditional taxonomy fails, DNA barcoding powerful well-known tool obtain reliable identifications through efficient markers. work, we used 16S rRNA marker assess preliminary Isognomon sp. Malleus specimens from different localities Southern Sea. Bayesian inference (BI) maximum likelihood (ML) methods were applied test monophyly phylogenetic linages clarify taxonomic positions, allowing complete overview spreading these bivalves particular, identified as Atlantic I. bicolor, highlighting previously suggested invasive migration patterns, (i.e., Lessepsian migration), must be reconsidered with stronger critical attention light currently occurring global changes.