EUTHEMIA was a nymph of the Aegean island of Kos (Cos) who insulted the goddess Artemis and was struck down by her arrows.
Euthemia was probably one of the Naiades--fresh-water nymphs that were believed to die if their springs dried up. Indeed the passage "snatched away alive by Persephone" suggests a spring lost beneath the earth.
Perhaps the daughter of a local RIVER-GOD
CLASSICAL LITERATURE QUOTES
Pseudo-Hyginus, Astronomica 2. 16 (trans. Grant) (Roman mythographer C2nd A.D.) :
"[Meropes of Cos] had a wife, Ethemea, of the race of Nymphae (Nymphs), who was struck with the arrows of Diana [Artemis] when she ceased worshipping her. At last she was snatched away alive by Proserpina [Persephone] to the Land of the Dead."
- Hyginus, Fabulae - Latin Mythography C2nd A.D.