Noun
ureotelism (uncountable)
(biochemistry) The excretion of excess nitrogen as urea
Firstly, all known diapsids are uricotelic, meaning they excrete uric acid as nitrogenous waste, and there is no known case of a diapsid re-evolving ureotelism, or the excretion of urea, even when they return to semi-aquatic lifestyles. Source: Internet
Therefore, turtles would have to be the only known case of a uricotelic reptile reverting to ureotelism. Source: Internet
Ureotelism appears to be the ancestral condition among primitive amniotes, and it is retained by mammals, which likely inherited ureotelism from their synapsid and therapsid ancestors. Source: Internet