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海南沼虾(Macrobrachium hainanense)是海淡水洄游虾类,在我国,分布于浙南瓯江中下游及两广、海南地区。肉眼区分雌雄虾最主要依据是雄虾第二腹足内肢内侧具有一细长棒状雄性附肢,而雌虾则无此附肢。雌虾在水温20℃左右,进行生殖蜕皮,然后,雌雄虾交配,雌虾抱卵。雌虾抱卵量2 000～10 000粒,随个体大小而异。卵椭圆形,长径0.55毫米,短径0.45毫米。在水温31℃的水族箱中,从雌虾抱卵到仔虾出膜约需11天。
Macrobrachium hainanense is a marine freshwater migratory shrimp, distributed in the middle and lower reaches of the Oujiang River in southern Zhejiang and in Guangdong, Guangxi and Hainan in China. Macroscopic distinction between male and female shrimp is the most important basis for the second gastropod line inside the male has a slender rod-shaped male appendages, while females do not have such appendages. Females in the water temperature of about 20 ℃, reproductive molting, and then male and female mating, females holding eggs. Females hold 2 000 to 10 000 eggs, depending on the individual size. Egg oval, long diameter 0.55 mm, short diameter 0.45 mm. In an aquarium at 31 ° C, it takes about 11 days to get rid of the eggs from the larvae to the larvae.