Keuthonymos (or Ceuthonymus) (Κευθωνυμος) is an ancient Greek spirit in mythology who is the father of Menoites (or Menoetes, Menoetius), who guarded the oxen of Hades. Keuthonymos is a mysterious daimon or spirit of the underworld, who lives in the realm of Hades. Keuthonymos is possibly the same as Iapetos, a Titan, and father of a certain Menoitios.
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- Emily Vermeule (1981). Aspects of death in early Greek art and poetry. University of California Press. p. 242. ISBN 978-0-520-04404-3.
- Thomas Keightley (1896). The Mythology of ancient Greece and Italy. George Bell and Sons. p. 322.