Question: what is the difference between mermaids and sea nymphs?
Answer: The legend of the mermaid was created by the myths of the Nereids and sea nymphs. While the nereids where usually depicted with legs, they were linked with mermaids. Also, as shapeshifters, the sea nymphs could assume the tails of fish. ... The Nereids were the guardians of sailors and the sea, but they had a darker side.