In the same year, Priosphenodon avelasi was described by Apesteguía and Novas in 2003, based on type specimen MPCA 300, a partially articulated adult skeleton from the Cenomanian fluvial sandstones of the Candeleros Formation in the Neuquén Basin.

described by Gentil et al. in 2019 comprises a fragment of 14.6 millimetres (0.57 in) long preserving nine teeth, presenting an acrodont implantation and a nearly straight anteroposterior linear arrangement.

The oldest record (the K. minimus type locality) of the genus comes from the La Paloma Member of the Cerro Barcino Formation of the Cañadón Asfalto Basin in north-central Patagonia, Argentina.

The same locality where Kaikaifilusaurus was found, has provided abundant fossils of lepisosteid fish, chelid turtles, lizards, neosuchian crocodyliforms, ornithopods, titanosaurian sauropods and diverse theropods including abelisaurids, carcharodontosaurids, and megaraptorans.

[5] The dinosaurs Gualicho shinyae, Argentinosaurus huinculensis, Mapusaurus rosae, Cathartesaura,[14] Ilokelesia,[15] and Skorpiovenator bustingorryi,[16] come from this formation.