Background The diversity of the sedimentary environment and molluscs is rich in the intertidal zone of the Yellow Sea and Bohai Sea. At present, many of the investigations focus on macromolluscs, while the diversity of micromolluscs is seriously underestimated.

The endemic Mediterranean bivalve Pinna nobilis is a typical example of an autogenic ecosystem engineer in sedimentary environments, as it modifies the substrate, creates new complex 3D habitats and concentrates various species, thus increasing local

The diversity of the sedimentary environment and molluscs is rich in the intertidal zone of the Yellow Sea and Bohai Sea. At present, many of the investigations focus on macromolluscs, while the diversity of micromolluscs is seriously underestimated.