According to the Folk-tales of the Kiwai Papuans, Erumia is an enormous, wonderful jelly-fish which lives on the reef called Téremúba-mádja, off the Gésovamúba point near Mawáta. She is the mother of all the ordinary jellyfish (édeéde), which are abundant on that reef. Many men have seen Erumia, and several have been stung by her («all same hot water he burn»). She can even sting a man to death. If a man sees some long slimy strings stretching towards him in the water as if trying to entangle him, he knows that they belong to Erumia and flees for his life.

Erumia is the patron of all the fish. The people do not swim at the Téremúba reef for fear of her. She appears to certain men in dreams and gives them some «lucky thing» which helps them to catch plenty of fish.

The Mawáta people are associated by their neighbours with Erumia, which is regarded as their ororárora. When, for instance, they visit some other place, they are sometimes received with the words, «Erumia people he come». A serial song describing a journey from Adíri, the country of the dead, gives some characteristic circumstances connected with a number of places, passing eastward, and of this song the following «verse» has reference to Erumia, «Oh, Bina súomóie Erumia súo rirou. — Oh, along mouth belong Bina river string belong Erumia he hang down» (876: p.202-203).