The black line is the digestive tract of shrimp, leading to the "stomach" of shrimp and the tail of shrimp excretion. So the black line contains shrimp excrement, which was not excreted before death.

Introduction:

Shrimp is a long-lived animal living in water, belonging to arthropod crustaceans, with a wide variety, including green shrimp, river shrimp, grass shrimp, crayfish, prawn, prawn, prawn, lobster and so on. ?

Morphological characteristics:

Shrimp is long and flat, with a calcareous exoskeleton, which is divided into two parts: chest and abdomen. The head and chest are covered with carapace. The abdomen consists of seven body parts. There is a serrated forehead sword and 1 double rotatable compound eyes with handles at the front end of the head breastplate. Shrimp breathes through gills, which are located on both sides of the head and chest and covered by crustaceans. Shrimp's mouth is at the bottom of the head and chest. There are two pairs of antennae in the head and chest, which are responsible for smell, touch and balance, respectively, and a chewing device composed of the lower jaw. There are also three pairs of jaw feet on the head and chest to help contain food, and five pairs of walking feet, which are mainly used for hunting and crawling. There are five pairs of swimming limbs and a pair of stubby tail limbs in the abdomen. The tail limb and the last abdomen are combined into a tail fan, which can control the swimming direction of shrimp.

Ghost shrimp:

A small freshwater shrimp. They are usually called ghost shrimp because they are completely transparent and even their internal organs can be clearly seen. In fishery production, it is mainly used as bait for fishing or often eradicated as an enemy of raising mussels. However, for pet lovers, they are fish food for larger fish. What's more, in recent years, ghost shrimp has been raised as a favorite pet ornamental fish because of its personal love. Besides being easy to feed, their peculiar shapes also attract people deeply.