求翻译：它头胸部较粗大，外壳坚硬，色彩斑斓，腹部短小，体长一般在20厘米～40厘米之间，重0.5公斤上下，是虾类中最大的一类。最重的能达到5公斤以上，人称龙虾虎。体呈粗圆筒状，背腹稍平扁，头胸甲发达，坚厚多棘，前缘中央有一对强大的眼上棘，具封闭的鳃室。主要分布于热带海域，是名贵海产品。中国已发现8种，以中国龙虾产量较大。根据营养专家黎黍匀分析，龙虾的预防疾病指数、生命力指数均低。是什么意思？

Its head and thorax coarse, hard shell, colorful, abdomen short, the general length of 20 cm to 40 cm, weight 0.5 kilos, is the largest class of shrimp. Most important to reach 5 kg or more, known as lobster tiger. Takes the shape of thick cylindrical, slightly flat belly back flat, well-developed c

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Its cephalothorax is thick, the outer covering is hard, color variegated, the abdomen is short, body long generally between 20 centimeters ~40 centimeters, about the weight 0.5 kilogram, is in the marcruran crustaceans biggest one kind.Heaviest can amount to above 5 kilograms, personal dragon goby.T

Its head chest more bulky, hard shell, a kaleidoscope of abdominal small form, body length usually between 20 cm ~40 cm, weighs 0.5 kg, is the largest category of shrimp. Most of 5 kg or more, it is called lobster and tiger. Rough cylinder, back, abdomen slightly flat, breastplate developed, thick s

Its head and thorax coarse, hard shell, colorful, abdomen short, th