Although some diapsids have lost either one hole (lizards), or both holes (snakes and turtles), or have a heavily restructured skull (modern birds), they are still classified as diapsids based on their ancestry.
Mada su neki diapsidi izgubili bilo jedan otvor (gušteri), ili oba otvora (zmije i kornjače), ili imaju znatno restrukturiranu lobanju (moderne ptice), oni se još uvek klasifikuju kao diapsidi na bazi njihvog porekla.