1. Species and appearance differences: Bombyx mori belongs to Bombycidae, with round or nearly triangular appearance, shiny shell surface, concentric wheel centers, yellow-brown or brown color, and white or blue-purple shell. The flower shell belongs to the genus Ruditapes, belonging to Claudioside order Claudioside. Small shape, oval shell, yellow-brown shell surface, black, brown, dark brown, dense color or reddish brown spots or patterns.

2. Differences in color and living habits: The shell surface of Meretrix meretrix is yellow-green, dark brown and black, and it grows in fresh water. The shell surface is yellowish brown with black, brown, dark brown, dense or reddish brown spots or patterns. It lives in a shallow sea area a few meters below the intertidal zone, and its main habitat is the sedimentary seabed.