She is the darkest and shadiest of the HARPIES. At least, if her name is anything to go by — it means literally ‘The Dark’.
Some sources claim she is the mother of BALIUS and XANTHUS, the two supernatural horses of ACHILLES. (Her other name — ‘Podarge’ — means swift of foot, which adds a certain credibility.) Other sources say AELLO was responsible. Either way, Wind God ZEPHYRUS was the dad, although it could all be a lot of hot air.
Note: she has no connection with CELAENO(2) as far as we know.