The genus name Psammonyx may refer to:

  • Chromista:
    • Psammonyx Döderlein, 1892 (Foraminifera, Ammovolummidae): accepted senior homonym
  • Animalia:
    • Psammonyx Jarrett & Bousfield, 1982 (Amphipoda, Tryphosidae): junior homonym, = replaced by Wecomedon Jarrett & Bousfield, 1982, as oldest available junior synonym