Grass shrimp, the scientific name of Penaeus monodon, also known as black shell shrimp, mollusca, Penaeidae. The frontal angle is 7-8/2-3. There are antenna spines, liver spines and upper stomach teeth in the head and breastplate, but there is no forehead and stomach ridge, and the liver ridge is obvious and straight. The lateral sulcus of frontal angle is short and does not exceed the middle of breastplate. Step five, the foot has no outer limbs. The horizontal spots of dark green, dark brown and light yellow are alternately arranged on the body, forming bright stripes on the abdomen. With strong vitality, delicious meat and large size, it is the largest species in the genus Penaeus. The largest female shrimp is 33 cm long and weighs over 500 grams. omnivorous

Shrimp is short and thick, and its whole body consists of head, chest and abdomen. The head and chest are connected together, and the back and sides are covered with a large piece of bone, which is called head breastplate or carapace. The head and chest are thick, the abdomen is thick, and the back is tapering. The frontal angle is located in the center of the front end of the head and chest, with a straight upper edge and a sharp end. The front end of the carapace has a sword-like protrusion, the upper edge is red 1 1~ 15, and the lower edge has 2~4 teeth.

There is a hard shell on the body surface of freshwater shrimp, which plays a role in protecting the body. Its whole body consists of 20 segments, including 5 segments of the head, 8 segments of the chest and 7 segments of the abdomen. There are five pairs of gait, the first two pairs are pliers and the last three pairs are claws. Among them, the second pair of walking feet of the male shrimp is particularly strong, and the appendage of the sixth abdominal segment has evolved into a powerful tail fan, which plays a role in maintaining the balance, lifting and retreating of the shrimp.