 The persistence of these reconstructed relationships even after the removal of aquatic characteristics points to their robustness.Below, the phylogenetic tree from the phylogenetic analysis published by Huang, Motani, and colleagues in 2019, in the description of "Chaohusaurus brevifemoralis", is partially reproduced.The appearance of ichthyosauromorphs was part of the recovery of marine ecosystems following the devastating Permian–Triassic extinction event.