Tritheledontidae, the tritheledontids or ictidosaurs,[1] is an extinct family of small to medium-sized (about 10 to 20 cm long[1]) cynodonts.

They were highly mammal-like, specialized cynodonts, although they still retained a few reptile-like anatomical traits.

Tritheledontids became extinct in the Jurassic period, possibly due to competition with prehistoric mammals such as the eutriconodonts.

The family Tritheledontidae was named by South African paleontologist Robert Broom in 1912.

[4] Cladogram after Ruta, Botha-Brink, Mitchell and Benton (2013):[5] †Cynognathia †Lumkuia †Ecteninion †Aleodon †Chiniquodon †Probainognathus †Trucidocynodon †Therioherpeton †Riograndia †Chaliminia †Elliotherium †Diarthrognathus †Pachygenelus †Brasilitherium †Brasilodon †Oligokyphus †Kayentatherium †Tritylodon †Bienotherium †Sinoconodon †Morganucodon Mammalia