Cryptodontia is a group of dicynodont therapsids that includes the families Geikiidae, Oudenodontidae, and Rhachiocephalidae.

It was first named in 1860 by English paleontologist Richard Owen.

Owen intended Cryptodontia to be a family, and the name was later changed to "Cryptodontidae" to reflect this ranking.

The name Cryptodontia was restored in 2009 when it was redefined as a larger clade containing several families of dicynodonts.

[1] Below is a cladogram from Kammerer et al. (2011) showing the phylogenetic placement of Cryptodontia: Eodicynodon Pylaecephalidae Eumantellidae Endothiodontidae Emydopidae Kingoriidae Cistecephalidae Myosauridae Rhachiocephalidae Oudenodontidae Geikiidae "Dicynodon" Lystrosauridae Shansiodontidae Kannemeyeriidae Stahleckeriidae Dinodontosauridae