1. Population description

Clams are small and medium-sized freshwater shellfish, also known as river clams, flat snails, sand clams, etc. In terms of biological classification, they belong to the biological kingdom and invertebrates. The general name for invertebrates of the Phylum Animalia, Class Bivalvia, Order Clamidae, and Clamidae. They are found in fresh water, brackish water and other water quality all over the country. They like to live in burrows on the bottom of mud, sand or fine sand, and have extremely strong Taking use value and economic value. 2. Morphological characteristics

Clam pearl oysters are medium in size, with thick and hard shells. The two shells are swollen. The appearance is slightly triangular, with slightly symmetrical sides, short rounded front side and slightly rounded rear side. The ventral edge is very curved and basically semi-circular, the back edge is slightly truncated, and the outer edge is round. The shell surface is earthy yellow-brown, light green, dark brown or jet black and glossy. The natural nacre layer is light purple or bright blue-purple and has Porcelain-like gloss, strong outer tendons, tan, obvious coat marks, and oval adductor muscle marks on the front, back, left, and right. 3. Distribution Scope

Clams are an important small and medium-sized freshwater economic shellfish. They are widely distributed in the waters of all continents outside Antarctica. In my country, they reach Heilongjiang in the north, Hainan in the south, Jiangsu and Zhejiang in winter, and Jiangsu and Zhejiang in the west. They are widely distributed in Sichuan and Shaanxi, and some types are also suitable for artificial breeding. For example, river clams are suitable for release and breeding on large and medium-sized water surfaces, and are also suitable for feeding and fertilizing on small and medium-sized water surfaces or ponds. 4. Living habits

Clams inhabit freshwater and saltwater rivers, lakes, ditches, ponds and other waters. They are especially common at the junction of saltwater and freshwater at river estuaries. They like to live on the mud bottom. They live in burrows on sandy or fine sandy bottoms. The larvae live in a depth of 1 to 2 cm. The adults can submerge in a depth of 2 to 20 cm. They are omnivorous and mainly feed on zooplankton. They lay eggs and are mostly dioecious. 5. What are the differences between clams and flower beetles

Generic differences: Although clams and flower beetles belong to the phylum Invertebrates, they belong to different families of Materia Medica. Generally speaking, clams belong to the order Clamidae of the order Clamidae, a bivalve class; and the flower clams also have many aliases, such as clams, yellow clams, sea clams, pink clams, oil clams, etc., and belong to the order Clamidae of the order Lavalbranchia. , it is obvious that they are two different animals.

Color difference: There is a difference in the color of clams and sixtieths. The color of clams is darker, usually tan or dark brown. In comparison, the color of sixtieth clams is more beautiful, and they may have different color lines. That is why they are famous as sixtieth clams and clams.

Differences in body shapes: The body shapes of clams and 60-year-olds are different. Comparing the two, the sixty-year-old is smaller, but if you only observe it with the human eye, it is not easy to see this difference.

Differences in appearance: The appearance of clams and flower shells is also different. Clam shells are usually nearly triangular, sometimes more circular. The shape of the flower carapace is different, closer to a square shape. The difference in appearance between the two is quite significant.