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“ echinoid : an echinoderm of the class Echinoidea , which includes the sand dollars and sea urchins . ”

“海胆：一种属于海胆纲的棘皮动物，包括沙钱和海胆.”

echinoderm having a flexible sausage-shaped body , tentacles surrounding the mouth and tube feet ; free-living mud feeders : sea cucumbers .

身体灵活形如香肠的棘皮动物；触须分布在嘴和管状脚的周围；自由生活的泥地食客：海参。

The echinoderm biomass in this area ( 6.18g / m ~ 2 ) is higher than that in the South China Sea and the East China Sea .

全区棘皮动物生物量6.18g/m~2，均较南海和东海的高；