Krill species are similar in appearance to small decapod shrimps, with a body length of 6 to 95 millimeters. The body can be divided into cephalothorax and abdomen. Cephalothorax body segments are completely covered by the cephalothoracic armor, cephalothoracic armor on both sides of the lower edge of the smooth or lateral teeth. The abdomen is divided into 7 segments, and some species have spines or ridges on the dorsal surface of the abdominal segments and 1 pair of lamellar spines on both sides of the end of the caudal segment. Appendages ****19 pairs, the first antennae double-branched type, peristome 3 segments, the morphology of each segment varies according to the species.

Extended information:

. p>Krill live in swarms, sometimes at densities of 10,000 to 30,000 per cubic meter. They feed on tiny phytoplankton, from which they convert energy from primary production to sustain their life cycle in their pelagic zone. Typically, krill grow to be up to 1 to 2 centimeters in length and 2 grams in weight, and have a lifespan of about six years.

Antarctic krill are concentrated in the Southern Ocean. They are distributed around the polar regions, with the highest densities being in the Atlantic region. It has been difficult to get accurate data about the stock of krill in the Southern Ocean. According to the 1977-1986 period by the Scientific Committee on Antarctic Research and the Scientific Committee on Oceanic Research and other international organizations joint sea survey, the Southern Ocean krill reserves of about 400 to 600 million tons. According to this estimate, if the annual catch of krill does not exceed 50 million tons, it will not affect the ecological balance of the Southern Ocean waters, and krill will grow and develop normally.

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