The crocodile's head is stuffed while the skin of the rest of its body is still attached.
The 44-year-old was stopped after taking a flight via St Petersburg from Mauritius, where he had bought the crocodile for $25 US as a gift for his mother.
Nile crocodiles are threatened with extinction and therefore stand on a list of protected species.
The man now faces a court process for attempting to smuggle illegal goods into the country.
The crocodile has been seized and will not be returned to him after the court case's conclusion.
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