Nymphs are a race of female nature spirits that tend to take on a form related to their environment (Example: While in forests: trees, in flower fields: flowers, in bodies of water: water). They can take on a human form with brown, orange, blue, green or aqua skin color. In the animated series a nymph named Syrinx has a family of male tree-like entities, if these creatures are male nymphs or not is never explained; these "males" can only take on a partially humanoid form (resembling trees or bushes with faces). The nymphs reside on Phil's Island and Philoctetes enjoys spending his time peeping on the females.
They reside on tropical islands and are in service to Gegenius, a giant monster who spares their lives in exchange for the life of sailors they lure to the island.
A female tree nymph who resides on Phil's Island. Unlike the rest of the nymphs she apparently enjoys Phil's company and seems to be in a relationship with him. However, she was upset with Phil when he forbid Hercules from dancing (considering it "un-manly"). She tells him he's just as stubborn and hard-headed as her father, who disapproves of her relationship with a satyr. She appeared in Hercules and the Muse of Dance.
Syrinx's family includes her father and three brothers. None of them are happy with her dating a satyr, especially not her father. Their attitudes changed when Phil saved her from a fire her father caused.
In Hercules and the River Styx. Styx is technically a Naiad, or fresh-water nymph.
In the original myth, nymphs were a female-only species.
If Phil's Island is Rhodes where the nymphs live then, the water nymph in the film could possibly be Rhode (daughter of Poseidon).