Family Cardiidae Lamarck, 1809

Remarks. For the genus Cerastoderma, the species status of Pontocaspian material is subject of debate where morphological and increasingly molecular arguments show the possibility of sibling species occurrences (Sromek et al. 2016). The genus Didacna is relatively well established, however much uncertainty exists over distinction between the genera Monodacna, Adacna, and Hypanis . The generic concepts have shifted through time. Only lately, Kijashko in Bogutskaya et al. (2013) treated Monodacna as a subgenus of Adacna . Büyükmeriç and Wesselingh (2018) discussed the distinction between the three genera and considered Monodacna, Adacna, and Hypanis as valid.