X. sloanii Kellogg, 1923 X. simplicidens Boessenecker & Geisler, 2023 Xenorophus is a genus of primitive odontocete from late Oligocene (Chattian) marine deposits in South Carolina.

Xenorophus was originally described on the basis of a skull from the Chandler Bridge Formation of South Carolina in the collections of the USNM.

[1] Later authors, but also Remington Kellogg who described the genus, classified it in the family Agorophiidae, which eventually became a repository for primitive odontocetes.

[2][3][4][5] A cladistic analysis by Mark Uhen published in 2008 recognized Xenorophus as belonging with Archaeodelphis and Albertodelphis in an odontocete clade more primitive than Agorophius or Simocetus, and named it Xenorophidae.

[6] Xenorophus was capable of echolocation like modern dolphins, judging from the cranial features of two other xenorophids, Echovenator and Cotylocara[7][8] and from the shape of its own skull.