In English folklore the asrai is a type of aquatic fairy that lives in seas and lakes and is similar to the mermaid and nixie. They are sometimes described as timid and shy, standing between two and four feet tall, or may be depicted as tall and lithe.
Tales from Cheshire and Shropshire tell of a fisherman who captured an asrai and put it in his boat. It seemed to plead for its freedom in an unknown language, and when the fisherman bound it the touch of its cold wet hands burned his skin like fire, leaving a permanent mark. He covered the asrai with wet weeds, and it continued to protest, its voice getting fainter and fainter. By the time the fisherman reached the shore the asrai had melted away leaving nothing but a puddle of water in the boat  for it will perish if directly exposed too long to the sun. Their inability to survive daylight is similar to that of trolls from Scandinavian folklore.
Other tales describe the asrai as having green hair and a fishtail instead of legs or may instead have webbed feet. They live for hundreds of years and will come up to the surface of the water once each century to bathe in the moonlight which they use to help them grow. If the asrai (usually depicted as female) sees a man she will attempt to lure him with promises of gold and jewels into the deepest part of the lake to drown or simply to trick him. However, she cannot tolerate human coarseness and vulgarity, and this will be enough to frighten her away.
Etymology and Origin
The etymology of the word asrai is unknown. "Ashray" is sometimes given as a spelling variant.
Their oldest known appearance in print was the poem "The Asrai" by Robert Williams Buchanan, first published in April 1872, and followed by a sequel, "A Changeling: A Legend of the Moonlight." Buchanan described them as nature-loving spirits who could not bear sunlight.
The second known mention of the asrai, and the first to explicitly describe them as beings from folklore, was Ruth Tongue's account in Forgotten Folk-Tales of the English Counties (1970). Tongue was an influential folklorist, but her accuracy has been called into question. She claimed to have grown up in Somerset, where she gathered most of her research, but this claim was later disproven. In "A Dictionary of English Folklore," Jacqueline Simpson and Stephen Roud state that "in Forgotten Folktales she gives only the vaguest hints as to where, when, and from whom she had obtained the stories; any notes she may have made at the time were lost in moves and fires.”
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- Tongue, Ruth (1970). Forgotten Folk-Tales of the English Counties. Routledge & Kegan Paul. pp. 24–26. ISBN 0710068336.
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- Simpson, Jacqueline, and Stephen Roud (2000). A Dictionary of English Folklore. Oxford University Press.