Common mussels do not have pearls.

Common mussels usually do not have pearls; only shellfish that secrete a nacreous layer produce pearls. When mussels live in the river, occasionally there will be some parasites or sand grains, caught between the outer coat membrane and the mesocarp, when the epidermal cells of the outer coat membrane are stimulated, they will secrete nacreous plasmid dramatically, which surrounds the sand grains or parasites, constituting a complete pearl capsule, and finally turns into a pearl.

Types of mussels

1, pleated crown mussels

Pleated crown mussels, also known as cockles, lakes mussels, mussels, mussels, etc., for the mussels of the family Crested Mussels, genus of freshwater benthic mussels, China's coasts are common, generally inhabiting the freshwater, slow-flowing and static waters of the lakes, rivers and canals and ponds, the mud bottom or sediment bottom. The bottom of the mud or mud and sand bottom.

2, the sail mussels

The sail mussels, also known as mussels, pearl mussels, freshwater pearl mussels, triangular mussels, etc., are widely distributed in Hunan, Hubei, Anhui, Jiangsu, Zhejiang, Jiangxi and other provinces, especially in China, as well as the distribution of medium-sized lakes in China's Dongting Lake is more.

3, dorsal horn toothless mussels

Dorsal horn toothless mussels, also known as mussels, mussels, round mussels, etc., China's rivers, lakes and marshes are distributed throughout the distribution of the meat is edible, but also for the fish, birds, bait and fodder for poultry, livestock, and some areas with freshwater pearl mussels.

4, back tumor Li mussels

Back tumor Li mussels, also known as hemp skin mussels, hemp crooked, etc., distributed in Hebei, Anhui, Jiangsu, Zhejiang, Jiangxi, Hubei, Hunan, Guangdong, and Guangxi, etc., especially in the Yangtze River in the middle and lower basins of the large and medium-sized lakes and rivers with high yield.

5, dome mussels

Dome mussels shell medium-sized, thin but hard shell, long oval shape, length greater than two times the height of the shell is asymmetric on both sides, the front of the shell is short and rounded, after the elongation of the shell is not, the end of the slightly narrow and flat, the surface of the shell is dark brown or black.