What is "ceuthonymus"

Ceuthonymus (or Keuthonymos) is a spirit in mythology who is the father of Menoites (or Menoetes, Menoetius). Ceuthonymus is a mysterious daimon or spirit of the underworld, who lives in the realm of Hades. Ceuthonymus is possibly the same as Iapetos, a Titan, and father of a certain Menoitios.