因针鼹鼠之独特，被定类为特殊的哺乳动物，属单孔类动物。单孔类动物只有针鼹鼠和鸭嘴兽。

The echidna is such a unique animal that it is classified in a special class of mammals known as monotremes, which it shares only with the platypus.

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因针鼹鼠之独特，被定类为特殊的哺乳动物，属单孔类动物。单孔类动物只有针鼹鼠和鸭嘴兽。

The echidna is such a unique animal that it is classified in a special class of mammals known as monotremes, which it shares only with the platypus.

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