BENTHESIKYME

an Ethiopian sea nymph, a goddess of the waves and a daughter of Poseidon and Amphitrite, the wife of king Enalos. She raised Eumolpus, son of Chione and Poseidon. (Apollodorus iii)

Her husband Enalos: of the sea, may have been Triton, the god of lake Tritonis in Libya and, like Glaucus, a marine divinity connected with the story of the Argonauts.

From Apollodorus iii

"Chione had connexion with Poseidon, and having given birth to Eumolpus unknown to her father, in order not to be detected, she flung the child into the deep.

But Poseidon picked him up and conveyed him to Ethiopia, and gave him to Benthesicyme (a daughter of his own by Amphitrite) to bring up. When he was full grown, Benthesicyme's husband gave him one of his two daughters. But he tried to force his wife's sister, and being banished on that account, he went with his son Ismarus to Tegyrius, king of Thrace, who gave his daughter in marriage to Eumolpus's son. But being afterwards detected in a plot against Tegyrius, he fled to the Eleusinians and made friends with them."