DIOGENEIA was the Naiad Nymph of a well or fountain of the city of Athens in Attika, southern Greece. She was a daughter of the nearby River Kephisos (Cephisus), and the wife of the Athenian lord Phrasimos.
Pseudo-Apollodorus, Bibliotheca 3. 196 (trans. Aldrich) (Greek mythographer C2nd A.D.) :
"Erekhtheus [King of Athens] married Praxithea, daughter of Phrasimos and Kephisos' daughter Diogeneia."
Pseudo-Apollodorus, Bibliotheca 3. 14. 8 :
"Pandion married Zeuxippe, his mother's [Praxithea's] sister."
- Apollodorus, The Library - Greek Mythography C2nd BC